Istanbul Technical University
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Cosmogenic exposure age record of emerged nearshore erratic boulders on the western Antarctic Peninsula
No full textAbstract The retreat of the Antarctic Peninsula Ice Sheet since the Last Glacial Maximum provides key insights into ice-sheet dynamics, climate interactions and sea-level fluctuations. Terrestrial cosmogenic nuclide (TCN) dating of glacial deposits on the western Antarctic Peninsula (WAP) offers valuable temporal and spatial information regarding this retreat. However, many erratic deposits are found near the present sea level on the WAP archipelagos, limiting the applicability of TCN dating. This is because some of these deposits were previously submerged and later emerged due to ongoing post-glacial isostatic uplift and global sea-level rise. Here, for the first time on the Antarctic Peninsula, we present TCN dating results for emerged erratic boulders and bedrock samples located below the post-glacial marine limit of the WAP. Samples were collected from three islands along a latitudinal range from 64°S to 68°S: Nansen Island in Wilhelmina Bay ( n = 4), Galindez Island in the Argentine Islands-Kyiv Peninsula region ( n = 5) and Horseshoe Island on the northern coast of Marguerite Bay ( n = 1). Our study indicates that nearshore boulder emergence occurred sometime between 1.4 ± 0.3 and 3.8 ± 0.3 ka ago on the WAP. The bedrock samples on Galindez Island provide somewhat older ages (17.9 ± 2.8 and 11.8 ± 1.9 ka), indicating the earliest emergence following deglaciation of the WAP. We discuss the challenges associated with sampling emerged erratic boulders along the Antarctic Peninsula shorelines and propose methods for overcoming these complications.https://doi.org/10.1017/s095410202510039
A UAV-Based Mixed RF/FSO System with RIS-Aided Reflection Modulation Multiple Access
No full texthttps://doi.org/10.1109/ict65093.2025.11046236https://doi.org/10.1109/ICT65093.2025.1104623
Assessing freshwater plumes, offshore freshened groundwater and the risk of salt intrusions in urbanised karstic groundwater systems using combined resistivity methods 
No full textGroundwater acts as a critical link between onshore and offshore environments, connecting freshwater systems to saline oceans.  With 40% of the world's population residing along coastlines, understanding coastal groundwater reserves is paramount. One open question involves the vital role of submarine groundwater springs in global hydrology, and how the distribution and groundwater flux can be better constrained across the coastline to better predict both groundwater discharge into the ocean and saltwater inflow into coastal aquifers. Especially urban areas pose unique challenges where water demand is high and groundwater exploration problematic since geophysical remote sensing techniques often interfere with surface and subsurface constructions (e.g. cables, pipelines etc.), making innovative approaches for groundwater exploration crucial for sustainable groundwater management.In this study, we aim to address the complex dynamics of coastal karstic groundwater systems in urban regions, where meteoric waters discharge into the ocean through coastal and submarine freshwater springs, while concurrently facing the risk of saltwater intrusions. Our investigations in the bay of Antalya (Turkey) aim to provide a comprehensive understanding of the land-ocean transition zone in the karstic groundwater systems and provide new tools for future groundwater monitoring in coastal regions.We employ advanced hydroacoustic and resistivity methods, combining onshore and offshore electrical resistivity tomography with electromagnetic measurements to bridge the gap between onshore and offshore domains. This integration of geophysical datasets enables us to (1) delineate karstic groundwater flow pathways from land to ocean, (2) identify coastal and submarine freshwater springs, and (3) assess the risk of saltwater intrusions along the coastline.The study showcases the potential of offshore geoelectric measurements as a tool for groundwater investigations in urbanized coastal regions. The proposed approach will facilitate exploration efforts for groundwater in urbanised karstic areas, but much more importantly will facilitate monitoring strategies to avoid intrusions of saltwater into freshwater aquifers. Our findings contribute valuable insights for water management strategies in Antalya, with implications for safeguarding todays and future freshwater resources.  https://doi.org/10.5194/egusphere-egu24-1999
HyperCMR: Enhanced Multi-contrast CMR Reconstruction with Eagle Loss
No full textAccelerating image acquisition for cardiac magnetic resonance imaging (CMRI) is a critical task. CMRxRecon2024 challenge aims to set the state of the art for multi-contrast CMR reconstruction. This paper presents HyperCMR, a novel framework designed to accelerate the reconstruction of multi-contrast cardiac magnetic resonance (CMR) images. HyperCMR enhances the existing PromptMR model by incorporating advanced loss functions, notably the innovative Eagle Loss, which is specifically designed to recover missing high-frequency information in undersampled k-space. Extensive experiments conducted on the CMRxRecon2024 challenge dataset demonstrate that HyperCMR consistently outperforms the baseline across multiple evaluation metrics, achieving superior SSIM and PSNR scores.MICCAI 2024 STACOM-CMRxReconhttps://doi.org/10.1007/978-3-031-87756-8_15https://dx.doi.org/10.48550/arxiv.2410.03624http://arxiv.org/abs/2410.03624https://doi.org/10.48550/arXiv.2410.03624https://research.utwente.nl/en/publications/fee39b7f-8fe5-47e6-bc7a-831ef3ef7ff
XGBoost Enhances the Performance of SAFE: A Novel Microwave Imaging System for Early Detection of Malignant Breast Cancer
No full textBackground/Objectives: Breast cancer is a significant global health concern, and early detection is crucial for improving patient outcomes. Mammography is widely used but has limitations, particularly for younger women with denser breasts. These include reduced sensitivity, false positives, and radiation risks. This highlights the need for alternative screening methods. In this study, we assess the performance of SAFE (Scan and Find Early), a novel microwave imaging device, in detecting breast cancer in a larger patient cohort. Unlike previous studies that predominantly relied on cross-validation, this study employs a more reliable, independent evaluation methodology to enhance generalizability. Methods: We developed an XGBoost model to classify breast cancer cases into positive (malignant) and negative (benign or healthy) groups. The model was analyzed with respect to key factors such as breast size, density, age, tumor size, and histopathological findings. This approach provides a better understanding of how these factors influence the model’s performance, using an independent evaluation methodology for increased reliability. Results: Our results demonstrate that SAFE exhibits high sensitivity, particularly in dense breasts (91%) and younger patients (83%), suggesting its potential as a supplemental screening tool. Additionally, the system shows high detection accuracy for both small (<2 cm) and larger lesions, proving effective in early cancer detection. Conclusions: This study reinforces the potential of SAFE to complement existing screening methods, particularly for patients with dense breasts, where mammography’s sensitivity is reduced. The promising results warrant further research to solidify SAFE’s clinical application as an alternative screening tool for breast cancer detection.https://doi.org/10.3390/cancers17020214http://dx.doi.org/10.3390/cancers1702021
Investigating Spatial-Behavioral Patterns in Hazards: A Virtual Reality Study as A Data Gathering Method
No full textAnalyzing multi-hazards requires a comprehensive approach, involving complexities in studying multiple hazards and challenges in visualizing numerous risks due to the abundance of information (Kappes, et.al.2012). Risk perception research, on the other hand, has emerged to aid decision-makers in understanding how people characterize and evaluate different hazards, anticipating behavioral responses, and guiding risk communication. Although the risk perception concept has been integrated into various behavioral theories applied to examine preparedness for numerous hazard types, there remains a gap in understanding which theories are suitable for examining multiple hazard types simultaneously (Gill & Malamud, 2017). Therefore, anthropogenic factors indirectly influencing multi-hazard risk assessment need addressing. Studying human behavior in multi-hazard scenarios presents inherent challenges, primarily due to the retrospective nature of analyses conducted after the event. The lack of direct observation during occurrences hampers the formulation of questions and modeling beforehand, limiting the ability to address perception and recall biases in real time. Despite these challenges, a thorough examination of catastrophes necessitates understanding not only how people behave but also delving into the underlying reasons for their behavior, a longstanding challenge in economics and social sciences (Wilson, 2017).Virtual Reality (VR) environments emerge as valuable tools for overcoming these challenges. VR facilitates a more natural interaction among participants, providing an ideal setting to explore complex behavioral dynamics in disaster scenarios, previously nearly impossible in controlled settings. Combining the internal validity of laboratory experiments with the external validity of field or natural experiments (Fiore et al., 2009), VR enables repeated experiments with large subject pools, a challenge in real disaster situations. This allows researchers to achieve realistic yet replicable results that traditional methods struggle to attain. In contrast to real-world disasters, VR experiments avoid participant attrition, a common issue in natural research studies introducing biases. Conducting numerous identical experiments with a significant number of participants allows researchers to subtly manipulate factors and interactions, exploring specific questions comprehensively. Participants in VR experiments can engage in multiple scenarios, facilitating the exploration of learning behavior beyond one-time event analyses. Fiore et al. (2009) emphasize that VR participants can experience long-term scenarios in a short time, generating multiple counterfactual scenarios.While traditional laboratories played a central role in advancing behavioral economics, VR is poised to be vital for inclusive multidisciplinary behavioral research in more realistic environments. It not only addresses methodological challenges associated with disaster research but also opens avenues for nuanced exploration of the reasons behind human behavior in disasters. This study examines the use of VR as an innovative tool for new risk assessment in complex contexts, considering behavioral differences and mobility preferences of participants with and without familiarity with the spatial environment.https://doi.org/10.5194/egusphere-egu24-19323https://research.utwente.nl/en/publications/920b85dd-4aa6-4415-a769-caed602d0cd
Exploring the Evolution of LARG Management: A Bibliometric Analysis in the Automotive Sector
No full texthttps://doi.org/10.11159/iceptp25.13
Strategic Environmental Awareness and Gender-Driven Policy
No full texthttps://doi.org/10.1007/978-981-96-7979-9_
Sustainable aviation fuels: Evaluating environmental and operational impacts
No full textBetween 2013 and 2018, commercial aviation saw a 70% increase in carbon dioxide (CO2) emissions, significantly outpacing United Nations projections. This alarming trend is anticipated to continue, with emissions potentially tripling by 2050, driven by economic expansion and an increasing dependence on fossil fuels. In 2022, the aviation industry’s energy consumption reached 12.1 MJ/RTK, with projections forecasting a 2.8 to 3.9-fold increase by 2040. Without a strategic shift towards sustainable alternatives, aviation emissions are expected to reach 2,000 megatons by mid-century, posing a severe threat to global climate stability. This study emphasizes the urgent need for the aviation sector to adopt high-energy, reliable alternative fuels that can mitigate its environmental impact. A comprehensive evaluation and comparison of potential alternative fuels are presented, focusing on their energy densities, production processes, and ecological footprints. The research highlights the potential of these alternatives to meet the industry’s energy demands while significantly reducing greenhouse gas emissions. Technological advancements in fuel production and aircraft propulsion are also explored, underscoring their role in achieving meaningful emissions reductions. The study argues that integrating sustainable practices and fostering innovation within the aviation sector is critical for ensuring long-term sustainability and resilience. By transitioning to alternative fuels and embracing new technologies, the aviation industry can address its environmental challenges and lead the way in global efforts to combat climate change and achieve net-zero emissions by 2050.https://doi.org/10.35208/ert.153197
A Numerical Study About Hygrothermal Performance of Traditional Timber Framed Infilled Exterior Wall
No full texthttps://doi.org/10.1007/978-3-031-87316-4_4