Istanbul Technical University
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Watershed Sustainability Index: Concept, Applications, and Future Directions
No full textSustainable water resource systems are essential for meeting society's present and future needs while preserving ecological integrity. Ensuring sustainable management of a basin involves taking into account its hydrological characteristics, along with its environmental, social, and political aspects. Watershed Sustainability Index (WSI) is employed that integrates hydrology, environmental factors, biodiversity, and policy considerations. Its holistic and multidimensional approach provides insights into the complex interactions shaping watershed dynamics and supports evidence-based decision-making processes. Despite its utility, the Watershed Sustainability Index faces several challenges and limitations, including issues with data availability and quality, indicator selection and weighting, and the incorporation of diverse stakeholder perspectives. Addressing these challenges necessitates continued collaboration among researchers, practitioners, and policymakers to refine the Watershed Sustainability Index methodology and enhance its relevance and robustness. Future research should focus on refining indicator frameworks, developing spatially explicit modeling approaches, and integrating emerging technologies like remote sensing and machine learning. Efforts to enhance scalability and transferability across different scales and contexts are crucial for supporting more effective watershed management strategies. This study provides a concise overview of the Watershed Sustainability Index by considering its conceptual framework, main applications and future perspectives.https://doi.org/10.2339/politeknik.163435
Exploring housing renewal through residential satisfaction: insights from the Istanbul case
No full textPurpose This paper aims to reveal to what extent, and through which factors, housing renewals and the year of building construction affect residential satisfaction. Design/methodology/approach Residents' subjective evaluations and satisfaction concerning their dwellings and residential environments are examined, with a specific reference to housing renewal implementations and the year of construction. The study is based on a survey conducted through social media using an online questionnaire, targeting residents of Istanbul's housing areas undergoing rapid urban transformation through single-building renewals. Findings The results indicate that residents living in buildings constructed more than 30 years ago have negative evaluations regarding the structural quality and earthquake resiliency of their dwellings. However, despite high levels of residential satisfaction in newer buildings, evaluations of functional and facade properties remain negative. These results indicate that the residential buildings built in the last 10 years and within the national renewal program are far from meeting the residents’ expectations regarding the interior quality of the dwellings. Originality/value This paper discusses the housing renewal issue from the residents’ perspective. The findings reveal suggestions for the implementation of housing renewals in order to increase residential satisfaction.https://doi.org/10.1108/ohi-06-2023-015
Ultrasound-induced modification of pea pod protein concentrate
No full textAgricultural by-products have emerged as valuable resources for the sustainable production of high-quality food ingredients. Ultrasound, a novel and environmentally friendly technology, is an effective physical method for solvent-free protein modifications. This study explores the conversion of pea pods as an agricultural by-product into value-added protein-based food ingredients with multifunctional properties enhanced by high-intensity ultrasound (US). Pea pod protein concentrate in the native form (PPPC-N) obtained by alkaline extraction/isoelectric precipitation was subjected to ultrasound-induced protein modification using response surface methodology at varying amplitude (40-80 %), time (2-20 min), and protein concentration (1-5 % w/v). The US process parameters were separately optimized based on maximum solubility, emulsification, and antioxidant activity. Protein concentrates were characterized at optimal conditions (80 % amplitude, 11 min, and 1 % protein; the desirability of 0.964) based on the maximum emulsification. The optimized PPPC by US (PPPC-US) exhibited a superior solubility performance compared to PPPC-N in the pH range of 2.0-9.0. The optimal US treatment enhanced the emulsifying attributes and foaming capacity of PPPC-N with an increase of 49 %. Moreover, oil binding capacity significantly increased while water binding capacity and foam stability decreased. Developing functional ingredients from pea pod proteins can open new possibilities in formulating innovative products.https://doi.org/10.1016/j.crfs.2025.101031https://pubmed.ncbi.nlm.nih.gov/40176880http://dx.doi.org/10.1016/j.crfs.2025.101031https://doaj.org/article/8914c76888354554bb8f1517b80478a
Effect of Non-Thermal Atmospheric Cold Plasma on Surface Microbial Inactivation and Quality Properties of Fresh Herbs and Spices
No full textCulinary herbs and spices are highly valued for their contribution to aroma, color, and overall flavor in traditional foods. Microbial inactivation in fresh herbs and spices is challenging due to their complex surface structures and dense natural microflora, which limit the effectiveness of conventional methods. Atmospheric cold plasma (ACP) is an innovative non-thermal technology with potential applications in the fresh spice industry. This study investigates the efficacy of ACP, generated using a practical, simple, and original system that allows uniform treatment without complex equipment, on microbial inactivation and quality attributes of fresh spices. Treatments of 1 and 3 min were applied, and their effects on natural microflora, Escherichia coli, and Pseudomonas syringae spp. were evaluated on the first day and after 7 days of storage. Results showed that 3 min treatments achieved higher reductions in natural microflora (2.91 log CFU g−1), E. coli (2.76 log CFU g−1), and P. syringae spp. (2.24 log CFU g−1) compared to 1 min treatments (1.87, 1.93, and 1.65 log CFU g−1, respectively). Different herbs exhibited varying responses to ACP, reflecting differences in leaf structure and chemical composition, which highlights the need for tailored treatment strategies. ACP treatment did not significantly affect water activity, color, or moisture content (except for rosemary, bay leaf, and thyme), nor total anthocyanin content (TAA), total phenolic content (TPC), total antioxidant capacity (TAC), or total flavonoid content (TFC). However, total chlorophyll content (TCC) and pH increased significantly in most samples (except rosemary and dill). Scanning electron microscopy (SEM) revealed that the tissue integrity of rosemary and mint was affected by ACP, although more than 50% of carvone in mint was preserved, and its concentration increased. The observed microbial reductions and 3–8-day shelf-life extension suggest meaningful improvements in safety and storage stability for industrial applications. Overall, ACP demonstrates promise as a safe, efficient, and scalable alternative to conventional decontamination methods, with broad potential for enhancing the quality and shelf life of fresh spices.https://doi.org/10.3390/foods14213617https://pubmed.ncbi.nlm.nih.gov/41227590/https://pmc.ncbi.nlm.nih.gov/articles/PMC12609300
Integrating Queuing Theory and GBM for Dynamic Resource Allocation in 6G Networks
No full text6G networks promise seamless connectivity and unprecedented advancements compared to previous generations. Small cells are at the core of 6G's success, which improves network coverage, reduces delays, and increases capacity by placing base stations close to users. However, the dense deployment of small cells in 6G networks introduces significant challenges, particularly in resource allocation due to huge state and action spaces. More specifically, resource allocation decisions must be computed for thousands of cells. Also, frequent resource reallocation due to high user mobility increases the algorithmic overhead. These challenges negatively impact critical performance metrics such as latency, throughput, and packet loss. To address these challenges, this paper proposes a dynamic resource allocation model that integrates queuing-theory-based small cell state determination with Gradient Boosting Machine (GBM) predictions. This integrated approach empowers dynamic resource adjustment by ensuring the timely allocation of bandwidth, computing power, and energy usage. The simulation results demonstrate the effectiveness of the proposed approach in terms of latency, throughput, and packet loss compared to conventional resource allocation methods.https://doi.org/10.18586/msufbd.1672775https://dergipark.org.tr/tr/pub/msufbd/issue/92761/167277
Erosion Suppression of Zinc Borate Filler in HTV Silicone Rubber Under AC Dry-Band Arcing
No full texthttps://doi.org/10.1109/tdei.2025.356316
Dışmerkez Çaprazlı Çelik Çerçevelerde Kapasite Tasarımı Yaklaşımının ve Deprem Performansının Zaman Tanım Alanında Doğrusal Olmayan Hesap Yöntemi ile Değerlendirilmesi
No full textBu çalışma kapsamında, Türkiye Bina Deprem Yönetmeliği-2018 (TBDY-2018)’de belirtilen boyutlandırma esaslarına uygun olarak tasarımı yapılan, her iki asal doğrultusunda yatay yüklerin süneklik düzeyi yüksek dışmerkez çaprazlı çelik çerçeveler tarafından karşılandığı yedi katlı bir ofis binasının deprem performansı, zaman tanım alanında doğrusal olmayan hesap yöntemi kullanılarak değerlendirilmiştir. Taşıyıcı sistemi oluşturan elemanların doğrusal olmayan davranışları için yığılı plastik davranış (plastik mafsal) modeli esas alınmıştır. Çalışmada, on bir farklı deprem yer hareketi kullanılarak toplam yirmi iki adet zaman tanım alanında doğrusal olmayan analiz gerçekleştirilmiştir. Değerlendirmede taban ve kat kesme kuvvetleri, göreli kat ötelenmeleri, çapraz ve kolonlarda oluşan iç kuvvet talepleri, bağ kirişlerindeki kesme kuvveti – yer değiştirme ve moment – dönme talepleri dikkate alınmıştır. Zaman tanım alanında doğrusal olmayan yirmi iki adet analiz sonucu elde edilen taleplerin ortalama değerleri esas alınarak, TBDY 2018’de dış merkez çaprazlı çelik çerçeveler için öngörülen kapasite tasarımı yaklaşımının yeterliliği araştırılmış ve bina taşıyıcı sisteminin deprem performansı değerlendirilmiştir.https://doi.org/10.24012/dumf.159204
Remote Sensing‐based Machine Learning Techniques for Mapping Gold‐Mineralized Alteration Zones in the Fatira Mine Area, Egypt
No full textAbstractIn the Fatira (Abu Zawal) mine area, located in the northern Eastern Desert of Egypt, fieldwork and mineralogical analysis, integrated with machine learning techniques applied to Landsat‐8 OLI, ASTER, and Sentinel‐2 multi‐spectral imagery (MSI) data delineate gold‐sulfide mineralization in altered rocks. Gold (Au) anomalies in hydrothermal breccias and quartz veins are associated with NE‐oriented felsite dykes and silicified granitic rocks. Two main alteration types are identified: a pyrite‐sericite‐quartz and a sulfide‐chlorite‐carbonate assemblage, locally with dispersed free‐milling Au specks. Dimensionality reduction techniques, including principal component analysis (PCA) and independent component analysis (ICA), enabled mapping of alteration types. Sentinel‐2 PC125 composite images offered efficient lithological differentiation, while supervised classifications, i.e., the support vector machine (SVM) of Landsat‐8 yielded an accuracy of 88.55% and a Kappa value of 0.86. ASTER mineral indices contributed to map hydrothermal alteration mineral phases, including sericite, muscovite, kaolinite, and iron oxides. Results indicate that post‐magmatic epigenetic hydrothermal activity significantly contributed to the Au‐sulfide mineralization in the Fatira area, distinguishing it from the more prevalent orogenic gold deposits in the region.https://doi.org/10.1111/1755-6724.1533
Progress in Desalination Composite Membranes: Perspectives and Research Gaps
No full text<p>The research community seeks new techniques and strategies for producing fresh water to overcome the scarcity of drinking water, in which the first alternative deals with removing salt ions and other trace compounds from brackish water and seawater due to its large availability. Membrane technologies, such as nanofiltration, reverse osmosis, membrane distillation, and pervaporation, are likely to be potential tools for selectively removing salt ions from seawater. Today, researchers are working to manufacture more selective, scalable, and productive desalination membranes. Therefore, this review reveals the most recent composite membranes applied in different membrane processes and their outcomes in seawater desalination over the last 5 years (from 2020 until now). Apart from reporting the most relevant membrane concepts, the mechanisms of transport and separation are reviewed in association with the unprecedented membrane separation properties. Finally, the current challenges and future directions are briefly provided for the development of next-generation composite desalination membranes.</p>https://doi.org/10.1021/acs.iecr.4c04512https://vbn.aau.dk/da/publications/02eec518-a05e-419e-b697-074f24cf4ba0https://www.scopus.com/pages/publications/10500341771
