Istanbul Technical University
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The Future And Security of The Metaverse
No full textAfter the concept of Metaverse was introduced and started to become popular, one of the topics that people were curious about was what this concept meant and why it was so popular. As people started to learn and accept the concept of Metaverse, the second issue that was curious was what the Metaverse would turn into, what kind of path it would follow, that is, its future. However, with the world's largest companies saying that we are in this game, the understanding of this concept growing day by day and constantly keeping it on the agenda brought the third question to the minds of those interested in the subject in a short time. With the Metaverse hosting many new and emerging technologies, how will privacy and security in cyberspace be ensured? The subject of this study aims to examine in detail the future development areas of Metaverse in general and the security risks that may be encountered in this environment.https://doi.org/10.56809/icujtas.153239
Temporal and chemical changes during the Late Cretaceous arc magmatism in the Western Pontides (Turkey) 
No full textDuring the Late Cretaceous, a 2700 km long magmatic arc extended from the Lesser Caucasus through the Pontides into Srednogorie, Timok, Banat, and Apuseni (ABTS) in the Balkans. We studied the arc volcanic rocks in three regions of the Western Pontides, and compared them to the other arc magmatic rocks from the Lesser Caucasus, Eastern Pontides and Balkans. Prior to the onset of the arc magmatism, the region underwent uplift and erosion. New and published geochronologic and biostratigraphic data indicate that magmatism in the Lesser Caucasus, Pontides and Balkans started during the Turonian (ca. 93 Ma), peaked in the middle Campanian (80–78 Ma), and subsequently became rare and sporadic after the late Campanian (ca. 75 Ma). The arc magmatism, characterized by typical subduction signatures, was mainly of middle to high-K calc-alkaline affinity. Late Cretaceous volcanism occurred in a submarine and extensional environment. Along the whole belt, the arc volcanic rocks are overlain by Maastrichtian to Paleocene marine limestones and sandstones, marking the end of the main phase of arc magmatism. However, in the Western Pontides, Maastrichtian limestone sequence includes a volcanic horizon with a U-Pb zircon age of ca. 71 Ma. The geochemistry of the Maastrichtian volcanic rocks is more diverse compared to the older arc volcanic rocks, including alkaline and calc-alkaline basalts, as well as adakitic dacites. The coeval initiation of arc magmatism along the 2700-km-long magmatic arc is associated with the acceleration of Africa-Eurasia convergence at ca. 96 Ma, which is also independently indicated by the beginning of intra-oceanic subduction, inferred from the ages of suprasubduction-zone ophiolites and sub-ophiolite metamorphic rocks in Anatolia. The end of the magmatic activity in the arc is associated with a marked decrease in the convergence rate during the Campanian.     https://doi.org/10.5194/egusphere-egu24-857
Next-Stitch Counting in Crochet Swatches via Multi-Class Semantic Segmentation
No full texthttps://doi.org/10.1109/ipta66025.2025.1122201
In vivo , in vitro , and in silico toxicology studies of nanoplastics and their modeling
No full textNanoplastics (NPs) are nanoscale plastic particles that pose possible risks to health and the environment. Therefore, the study of their toxicity is critical for regulating their use, traceability, and impact assessment. Despite their prevalence in the life cycle, research on NP toxicity remains limited due to their diverse sources, routes of exposure, and increasing presence in nature. Moreover, regulatory frameworks lack adequate characteristic values to detect NPs in food and the environment, and there are currently no defined thresholds for harmful particles. This review examines key parameters in toxicity studies of NPs, focusing on <i>in vivo</i>, <i>in vitro</i>, <i>in silico</i>, and modeling approaches, as well as uptake pathways. NP analysis involves three basic steps: pretreatment, identification, and quantification. In these steps, parameters such as size, shape, zeta potential, surface charge, and density play important roles. Combining these approaches offers complementary insights, improving the understanding of NP toxicity. These findings underscore the need for comprehensive toxicity studies to inform regulations and reduce the risks associated with NPs in various contexts.https://doi.org/10.1080/15376516.2025.2546518https://dx.doi.org/10.6084/m9.figshare.30084662.v1https://dx.doi.org/10.6084/m9.figshare.3008466
Corrosion Behavior and Microhardness of a New B4C Ceramic Doped with 3% Volume High-Entropy Alloy in an Aggressive Environment
No full textThe aim of this paper is to study both the mechanical and chemical properties of a new material composed of B4C doped with 3% volume of CoCrFeNiMo HEA by the spark plasma sintering technique. Scanning electron microscopy and microhardness were used to characterize the composite microstructure and hardness. Corrosion behavior was studied by corrosion potential, corrosion rate and electrochemical impedance spectroscopy, where the equivalent circuit was obtained, characterized by the presence of the Warburg element. The addition of HEA resulted in a more compact microstructure, filling pores and inhibiting ceramic grain growth. A microhardness statistical analysis revealed that the sample followed a normal distribution, which suggests that the sample has a homogeneous structure. The doped material exhibits excellent corrosion resistance in artificial seawater, where its chemical interaction occurs in two steps, with an important diffusional component. This study highlights the potential for use in environments where both corrosion resistance and mechanical strength are critical factors.https://doi.org/10.3390/met15010079http://hdl.handle.net/10553/135868https://doaj.org/article/1152e34a111f46c59d72bd3da89aee1
Radar Cross-Section Shadowing: Novel Task Sharing Concept for Manned-Unmanned Teaming
No full texthttps://doi.org/10.1109/ccta53793.2025.11151505https://doi.org/10.1109/CCTA53793.2025.1115150
Driving Factors of Oxalic Acid and Enhanced Role of Gas-Phase Oxidation under Cleaner Conditions: Insights from 2007–2018 Field Observations in the Pearl River Delta
No full textAbstract. Secondary organic aerosol (SOA) is a dominant constituent of fine particulate matter, exerting significant impacts on both climate and human health. Oxalic acid (C2), a key end-product formed from the oxidation of volatile organic compounds, can provide insights into the formation mechanism of SOA. Thus, long-term measurements of C2 and related compounds help understand the changes in SOA formation with decreasing pollutant levels. In this study, C2 and its homologs, along with five primary anthropogenic source markers and three SOA markers, were measured in the Pearl River Delta (PRD) during 2007–2018. The concentrations of C2 and its homologs did not exhibit significant downward trends, despite substantial reductions in anthropogenic emissions, for example, biomass burning (−11 % yr−1), vehicle emissions (−17 % yr−1), and cooking emissions (−7 % yr−1). Correlation analysis revealed that aerosol liquid water content (ALWC) and Ox (O3 + NO2) were the main drivers of C2 variation. Moreover, the relative contribution of biogenic SOA increased under cleaner conditions. A machine learning model was applied to quantify the contributions of anthropogenic precursors emission, biogenic precursors emission, aqueous-phase oxidation processes, and gas-phase oxidation processes to C2 variability. As pollution levels declined, the contribution of gas-phase oxidation increased from 24 % to 48 %, whereas that of aqueous-phase oxidation declined from 35 % to 20 %. This shift indicated a transition from aqueous-phase to gas-phase pathways in C2 and SOA formation. Our findings highlight the increasing importance of gas-phase oxidation and underscore the need for effective ozone control strategies to further reduce SOA in the future.https://doi.org/10.5194/egusphere-2025-4624https://egusphere.copernicus.org/preprints/2025/egusphere-2025-4624
Enhancing output in open-pit coal mining: The influence of front loading geometry on machinery functionality
No full textThis study examines the productivity of excavation and haulage equipment in overburden removal operations at the Borneo Indobara site, with a primary focus on optimizing front-loading geometry, improving material flow, and enhancing equipment performance through advanced modeling and real-time monitoring. Particular emphasis was placed on the optimization of front-loading geometry, material flow dynamics, and equipment configurations to enhance overall operational efficiency and reduce inefficiencies across excavation cycles. A novel framework integrating machine learning, metaheuristic algorithms, and IoT-enabled real-time monitoring was implemented to predict productivity, improve bucket fill factors, and reduce cycle times. Results demonstrated that optimal front dimensions and innovative loading patterns significantly increased productivity. Gradient Boosting and Particle Swarm Optimization were employed for precise modeling and resource allocation, while dynamic simulations validated the proposed solutions. The findings highlight the potential for advanced data-driven methods to mitigate inefficiencies and enhance performance in open-pit mining operations.https://doi.org/10.1177/1063293x25136119
Development of an electrochemical sensor using molecularly imprinted polymers for the specific determination of the antiretroviral drug ritonavir
No full texthttps://doi.org/10.1007/s00604-025-07427-zhttps://avesis.kocaeli.edu.tr/publication/details/f4c23450-3653-4bd6-916f-bc55f109a58e/oa
Microstructure-Corrosion behavior of Laser powder bed fusion - AlSi10Mg produced using synchronous scanning strategy (SSS)
No full textThis study investigates the influence of the Synchronous Scanning Strategy on the microstructural characteristics and corrosion behavior components fabricated via the LPBF process. Electrochemical corrosion tests in 3.5 wt.% NaCl solution demonstrates that SSS-fabricated samples, particularly samples, exhibit significantly improved corrosion resistance compared to their traditionally scanned counterparts. These improvements are attributed to the homogeneous microstructure and reduced potential difference between Al and Si phases, which minimizes local galvanic effects. The results establish a clear link between scanning strategy and corrosion resistance, underlining the potential of SSS for optimizing LPBF processes in applications where electrochemical stability is critical.https://doi.org/10.1177/0267083625137608