WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7150
Browse
96 results
Search Results
Now showing 1 - 10 of 96
Article Citation - WoS: 7Citation - Scopus: 9A Holistic Overview of the Applications of Grace-Observed Terrestrial Water Storage in Hydrology and Climate Science(Springer, 2025) Khorrami, Behnam; Gunduz, OrhanTerrestrial Water Storage (TWS) represents a vital element of the hydrological cycle, with its fluctuations significantly impacting the climate of the Earth and its ecological balance. Since its launch in 2002, the Gravity Recovery and Climate Experiment (GRACE) satellite mission has revolutionized the ability to observe and analyze large-scale mass changes within Earth's system components. This paper offers a comprehensive and current overview of GRACE satellite gravimetry, highlighting its relevance to hydrological and climate-related studies. It outlines the fundamental measurement principles of the GRACE mission, provides an in-depth explanation of GRACE data products (including spherical harmonic and mascon solutions), examines emerging trends in GRACE-based research, and reviews key applications in hydrology and climate science. Additionally, it addresses the major challenges in utilizing GRACE data and explores promising avenues for future research and applications.Article Vision Transformers-Based Deep Feature Generation Framework for Hydatid Cyst Classification in Computed Tomography Images(Springer, 2025) Sagik, Metin; Gumus, AbdurrahmanHydatid cysts, caused by Echinococcus granulosus, form progressively enlarging fluid-filled cysts in organs like the liver and lungs, posing significant public health risks through severe complications or death. This study presents a novel deep feature generation framework utilizing vision transformer models (ViT-DFG) to enhance the classification accuracy of hydatid cyst types. The proposed framework consists of four phases: image preprocessing, feature extraction using vision transformer models, feature selection through iterative neighborhood component analysis, and classification, where the performance of the ViT-DFG model was evaluated and compared across different classifiers such as k-nearest neighbor and multi-layer perceptron (MLP). Both methods were evaluated independently to assess classification performance from different approaches. The dataset, comprising five cyst types, was analyzed for both five-class and three-class classification by grouping the cyst types into active, transition, and inactive categories. Experimental results showed that the proposed VIT-DFG method achieves higher accuracy than existing methods. Specifically, the ViT-DFG framework attained an overall classification accuracy of 98.10% for the three-class and 95.12% for the five-class classifications using 5-fold cross-validation. Statistical analysis through one-way analysis of variance (ANOVA), conducted to evaluate significant differences between models, confirmed significant differences between the proposed framework and individual vision transformer models (p<0.05\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p < 0.05$$\end{document}). These results highlight the effectiveness of combining multiple vision transformer architectures with advanced feature selection techniques in improving classification performance. The findings underscore the ViT-DFG framework's potential to advance medical image analysis, particularly in hydatid cyst classification, while offering clinical promise through automated diagnostics and improved decision-making.Article Citation - WoS: 1Staging Nişantaşı: Cultural Conflicts and Ideological Representations of Urban Space in Turkish Tv Culture(Springer, 2025) Catalbas, Zeynep Ceylan Gezer; Akpınar, İpek; Akpinar, IpekThis paper examines how urban spaces become sites of ideological contestation through their representation in popular media, focusing specifically on Ni & scedil;anta & scedil;& imath;, a historically significant neighborhood in Istanbul that embodies the class tensions within T & uuml;rkiye's modernization narrative. Drawing on cultural geography as a theoretical framework, the study analyzes how this distinctive urban space functions as both physical setting and symbolic element in post-2000 Turkish television dramas. Since the expansion of private broadcasting, these TV series have emerged as powerful agents in shaping public consciousness about space, class, and identity. Through semiotic analysis of selected programs, this research reveals how Ni & scedil;anta & scedil;& imath;'s portrayal constructs and reinforces social class distinctions in contemporary Turkish society. The findings demonstrate that urban geography serves as a reflective surface for cultural and social conflict, with television representations amplifying Ni & scedil;anta & scedil;& imath;'s multi-layered spatial identity formed through historical processes, societal dynamics, and personal narratives. By connecting these representations to broader patterns of class differentiation in T & uuml;rkiye, this study contributes to our understanding of how media portrayals of urban spaces simultaneously reflect and reinforce class distinction through collective social imaginaries.Article Citation - WoS: 1Citation - Scopus: 1Fabrication of Electrospun Polycaprolactone Nanofibrous Mats Loaded With Purple Basil Extract (Ocimum Basilicum L.) as Colorimetric Ph Indicator Films(Springer, 2025) Erez, Elif; Eroglu, Ahmet Emin; Bayramoglu, BesteIntelligent packaging with colorimetric pH indicators revolutionizes traditional food packaging by enabling real-time food quality monitoring. This study used electrospinning to develop pH indicator films from polycaprolactone (PCL) incorporating purple basil extract (PBE). Nanofibrous films containing 0.2% PBE (PCLN_0.2PBE), 0.4% PBE (PCLN_0.4PBE), and 0.6% PBE (PCLN_0.6PBE) were fabricated using different electrospinning conditions. The PCLNs fabricated with a voltage of 20 kV and a flow rate of 1.6 mL/h exhibited the most uniform and bead-free morphology according to scanning electron microscopy. The chemical, thermal, mechanical, and wetting characterization of the films was performed by Fourier transform infrared spectroscopy, differential scanning calorimetry, thermal gravimetric analysis, texture analysis, and contact angle analysis, respectively. Both PCLN_0.4PBE and PCLN_0.6PBE films displayed fast (4-5 s) and clear color transitions (Delta E > 3.5) to successive pH buffers within the range critical for food deterioration, while they exhibited excellent color changes (Delta E > 5) for pH variations of at least two units. The PCLN_0.6 PBE film displayed a Delta E of similar to 5 in only 5 min of exposure to ammonia vapor, whereas PCLN_0.4PBE showed a similar color change for over 15 min. The interaction between the films and acidic and alkaline semi-solid foods was simulated using gelatin gels at pH 2.5 and 11, respectively. Both films displayed significant color transitions (Delta E > similar to 9) within 15 min of contact with the gels, with the response from PCLN_0.6 PBE being more pronounced. The color stability in both films was maintained for up to 14 days at 4 degrees C, offering potential early warnings against food spoilage. PBE release was evaluated against different food simulants. The highest release occurred in 50% ethanol; the films demonstrated resistance to 3% acetic acid. The findings indicate that electrospun PCL films integrated with PBE have a promising potential to serve as colorimetric pH indicators for monitoring the freshness of food products.Article Citation - WoS: 2Vis-Assist: Computer Vision and Haptic Feedback-Based Wearable Assistive Device for Visually Impaired(Springer, 2025) Dede, Ibrahim; Gumus, AbdurrahmanVisual impairment affects millions of people worldwide, posing significant challenges in their daily lives and personal safety. While assistive technologies, both wearable and non-wearable, can help mitigate these challenges, wearable devices offer the advantage of hands-free operation. In this context, we present Vis-Assist, a novel wearable visual assistive device capable of detecting and classifying objects, measuring their distances, and providing real-time haptic feedback through a vibration motor array, all using an integrated low-cost computational unit without the need for external servers. Our study distinguishes itself by utilizing haptic feedback to convey object information, allowing visually impaired individuals to discern between 19 different object classes following a brief training period. Haptic feedback offers an alternative to audio that doesn't block hearing and can be used alongside it, serving as a complementary solution. The performance of the developed wearable device was evaluated through two types of experiments with four participants. The results demonstrate that users can identify the location of objects and thereby prevent collisions with obstacles. The experiments conducted demonstrate that users, on average, can locate a predefined object, such as a chair, within a 40 m2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\hbox {m}<^>{2}$$\end{document} vacant space in under 94 seconds. Furthermore, users exhibit proficiency in finding objects while navigating around obstacles in the same environment, achieving this task in less than 121 seconds on average. The system developed here has high potential to help the self-navigation of visually impaired people and make their daily lives easier. To facilitate further research in this field, the complete source code for this study has been made publicly available on GitHub.Editorial Editorial: Advancing Biotechnology in Turkiye: a Dedication To All Women(Springer, 2025) Cadirci, Bilge Hilal; Buyukkileci, Ali Oguz; Binay, BarisArticle Citation - WoS: 4Citation - Scopus: 4Optimization of Resource-Aware Parallel and Distributed Computing: a Review(Springer, 2025) Czarnul, Pawel; Antal, Marcel; Baniata, Hamza; Griebler, Dalvan; Kertesz, Attila; Kessler, Christoph W.; Rakic, GordanaThis paper presents a review of state-of-the-art solutions concerning the optimization of computing in the field of parallel and distributed systems. Firstly, we contribute by identifying resources and quality metrics in this context including servers, network interconnects, storage systems, computational devices as well as execution time/performance, energy, security, and error vulnerability, respectively. We subsequently identify commonly used problem formulations and algorithms for integer linear programming, greedy algorithms, dynamic programming, genetic algorithms, particle swarm optimization, ant colony optimization, game theory, and reinforcement learning. Afterward, we characterize frequently considered optimization problems by stating these terms in domains such as data centers, cloud, fog, blockchain, high performance, and volunteer computing. Based on the extensive analysis, we identify how particular resources and corresponding quality metrics are considered in these domains and which problem formulations are used for which system types, either parallel or distributed environments. This allows us to formulate open research problems and challenges in this field and analyze research interest in problem formulations/domains in recent years.Article Citation - WoS: 1Citation - Scopus: 1Efficiency Evaluation of Optimal Tlcd and Tmd for the Seismic Response Reduction of Buildings Considering Soil-Structure Interaction Effect(Springer, 2025) Roozbahan, Mostafa; Masnata, Chiara; Turan, Guersoy; Pirrotta, AntoninaTuned Mass Dampers (TMDs) and Tuned Liquid Column Dampers (TLCDs) are widely recognized passive vibration control devices used to reduce structural vibrations. While TMDs have been extensively studied for mitigating the seismic responses of multi-story buildings considering Soil-Structure Interaction (SSI), the efficiency of TLCDs in these conditions remains largely unexplored. Furthermore, a direct comparison of these devices under similar conditions has not been conducted. Then, to address these gaps, this study investigates the efficiency of TLCDs and compares them to TMDs in reducing seismic-induced vibrations, focusing on the influence of SSI. The control performance of both devices depends on various parameters, primarily the frequency and damping ratios. Therefore, the Mouth Brooding Fish (MBF) metaheuristic algorithm is applied to optimize these parameters, accounting for SSI effects. To evaluate the different efficiency between TMDs and TLCDs under SSI conditions, three types of shear buildings are considered: an eight-story, a sixteen-story and a forty-story structure. The seismic responses of the uncontrolled, TMD-controlled, and TLCD-controlled buildings are examined under twenty-two far-field and fourteen near-field earthquakes, considering both fixed-base and flexible-base scenarios. Results indicate that while both devices significantly reduce seismic responses, TMDs generally outperform TLCDs, particularly in taller buildings where the impact of SSI is more significant. Further, this study highlights that neglecting SSI in the design of these devices may lead to an overestimation of their effectiveness, especially in softer soils, emphasizing the importance of considering SSI in the optimization process for accurate and reliable outcomes.Article Citation - WoS: 2Application of Fractional Calculus-Based Anomalous Diffusion Model for Drying Analysis of Large Grapes Subjected To Micro-Perforation Pretreatment(Springer, 2025) Koroglu, Ebru; Berk, Berkay; Unluturk, SevcanThe study aimed to assess the potential of using needle micro-perforation pretreatment at various piercing lengths as an alternative to dipping in alkaline liquor solution for the hot air drying process of large grapes at temperatures of 60, 70, and 80 degrees C. Fick's second law and anomalous diffusion model based on the fractional calculus approach were used to analyze the drying curves and estimate effective diffusivity (D-eff). Needle micro-perforation on drying kinetics and some physicochemical properties (water activity, pH, titratable acidity, rehydration rate, shrinkage ratio, and color) of hot air dried Kavacik grapes (Vitis vinifera L. cv Alphonse Lavall & eacute;e) were investigated. The anomalous diffusion model fit the experimental data better and revealed super-diffusive behavior (alpha > 1). The effective diffusivity coefficients varied between 1.00 x 10(-10) to 6.47 x 10(-10) m(2)/s. The pretreatment at various piercing lengths showed no significant impact on water activity and color (P > 0.05). However, it did have a significant effect on pH, titratable acidity, rehydration rate, and shrinkage degree (P < 0.05). MG1.5 drying conditions at 60 degrees C were found to be the most suitable process conditions for achieving energy-efficient drying (high D-eff: 3.87 x 10(-10) m(2)/s) of grapes while preserving their highest-quality attributes related to drying (a(w): 0.54, RR: 1.95, pH: 4.31, Delta E: 3.38 and SR: 0.98). The results revealed that the needle micro-perforation pretreatment provided better color and water activity properties in dried grapes, and the drying time was reduced at even low temperatures. It has been shown that micro-perforation can be an environmentally friendly alternative method to chemical pretreatment in grape drying.Article Valorizing Sugar Industry Byproduct Through Microalga for Pigment Production(Springer, 2025) Engin, Iskin; Uzuner, SibelCurrently, consumers are seeking ways to obtain natural food colorants, and food supplements. Microalgal food colorants and supplements have become established in the food industry due to their ability to generate substantial biomass rich in polysaccharides, pigments, lipids, vitamins, and other bioactive compounds. However, the high costs associated with microalgal cultivation have gained interest in more economical alternatives. This study investigated the potential of using vinasse, a byproduct of the sugar industry, as a nutrient source to produce biomass, chlorophyll, and carotenoids with Parachlorella kessleri SAG211-11 h. The effects of culture conditions (vinasse concentration, light intensity and light/dark cycle) on chlorophyll a (Chl a), chlorophyll b (Chl b), and carotenoid content were investigated using Response Surface Methodology. The results showed that light intensity and light/dark cycle had a significant effect, especially on Chl a content (p < 0.05). Light intensity also showed a significant effect on Chl b and carotenoid content (p < 0.05). Response optimization was conducted under conditions of 5% vinasse concentration, 110 mu mol photons m(-2)s(-1), and 16:8 light dark cycle, yielding a Chl a content of 10.89 +/- 0.14 mg/L, Chl b content of 7.25 +/- 1.12 and carotenoid content of 2.79 +/- 0.94 mg/L. These results revealed that the chlorophyll content of P. kessleri cells can be enhanced under mixotrophic conditions by changing cultivation conditions with the usage of vinasse-based medium. Meanwhile, this research highlights vinasse as a sustainable carbon source for the cultivation of P. kessleri SAG211-11 h cells for chlorophyll and carotenoid production.