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A Novel Contingency Analysis Toolbox Developed by the Python API of PowerFactory
No full texthttps://doi.org/10.1109/ias62731.2025.11061461https://doi.org/10.1109/IAS62731.2025.1106146
Geology, petrography and emplacement conditions of the Esenköy Pluton (NW Anatolia)
No full textOne of the least studied plutons in NW Anatolia, the Esenköy pluton intruded into the Palaeozoic Armutlu metamorphics. Along its southwestern boundary with the Esenköy pluton, basement rocks are found as "roof pendants". Both the Esenköy pluton and the Armutlu metamorphics are cut by aplite and diorite porphyry dykes. The pluton is mainly granodioritic in composition and is made up of 45-50% plagioclase, 25-30% quartz, 12-15% alkali feldspar, 6-9% hornblende, and 3-5% biotite. It exhibits predominantly holocrystalline porphyritic texture, and graphic-granophyric textures are also widespread throughout the main plutonic body. Diorite porphyry dykes display micro-granular porphyritic texture, while aplite dykes commonly show micro-granular texture.Chemical analyses of plagioclase and amphibole minerals in granodiorite samples reveal that plagioclases are predominantly andesine (An35-50) in composition. Zoned plagioclases generally show normal zoning with a decrease in calcium ratios from the core to the rims of the crystals. Amphiboles are all calcic in composition and are represented by magnesio-hornblende. Geothermobarometric calculations, using the chemistry of amphiboles and plagioclases from the same samples, yield pressure values ranging from 1.12 to 1.41 kbar and temperature values ranging from 741 to 787 °C. These temperature and pressure conditions suggest that the Esenköy pluton is emplaced at depths of 3.37-4.23 km within the crust. Contact relationships, textural properties and geothermobarometric calculations collectively indicate that the Esenköy pluton is an epizonal pluton that was emplaced into shallow levels of NW Anatolian crust.https://doi.org/10.5194/egusphere-egu24-67
Petrographical And Geochemical Characteristics of The Zeolitic Akdere Tuff (Demirci, Western Anatolia)
No full textOne of the important Neogene basins of Western Anatolia (Turkey) is the NE-SW trending Demirci Basin. The Miocene sequence, consisting of approximately 1000 m thick clastics and volcanics, is unconformably located on the Paleozoic-Menderes Metamorphic Massif (gneiss, schist, marble). The lower part of Miocene sequence contains block–pebble–sand size of clastics. They are continued upward with sandstone, claystone, marl, limestone, mudstone, and shale lithologies laterally transition with pyroclastic rocks at the top. Pyroclastic rocks (Akdere Tuff) are covered by a lacustrine unit consisted of sandstone, mudstone, bituminous shale limestone and tuffite. Akdere tuff, with rhyodacite character, light beige-gray-green color, 10-70 m thickness, is highly zeolitized (heulandite-clinoptilolite). At the bottom of the tuff unit, there are 25-30 m thick, fine-coarse grained, pumiceous, glassy, and glassy-crystalline ash tuffs containing rare lithic fragments. These are overlain by 20-25 m thick glassy dust-ash tuffs. At the top there is a 5 m thick pumicite level with lateral transitions. Zeolitic Akdere tuff petrographically contains small and rare amounts of mineral and lithic fragments in a matrix consisting of glass fragments with concave, sharp straight or curvilinear edges and rarely pumice fragments. Mineral fragments (2-25 %) are feldspars (albite-oligoclase type of plagioclases and K-feldspar) quartz, biotite, muscovite, amphibole, and opaque minerals. According to the X-ray diffraction (XRD) results, the mineralogical composition throughout the samples is 'heulandite-clinoptilolite (hul-cpt) + opal-CT + opal-A + smectite + illite-mica + quartz + feldspar’. The heulandite-clinoptilolite ratio in the samples examined varies between 0-95 percent. The glassy groundmass of the tuffs is almost completely zeolitized. Heulandite-clinoptilolite grains, formed by the transformation of volcanic glass, are in the form of monoclinic plates, shorter than 15 µm according to the results obtained from scanning electrone microscope (SEM) studies. SEM studies also showed that devitrification of volcanic glass formed firstly a gel-like phase before the formation of heulandites-clinoptilolites. Cationic values ​​(Si/Al and Na+K/Ca+Mg ratios) taken from heulandite-clinoptilolite grains by Energy dispersive X-ray spectroscopy (SEM-EDX) gave the composition of both heulandite and clinoptilolite. However, thermal stability results indicated clinoptilolite, and clinoptilolite did not deteriorate at 550 oC. Whole-rock chemical values ​​and some chemical parameters of the zeolitic Akdere Tuff are as follows. SiO2: 68.45-76.50 %, Al2O3: 10.10-14.30 %, SİO2/Al2O3: 4.82-7.19, K2O: 1.34-4.46 %, Na2O: 0.13-2.92 %, CaO: 0.70-2.92 %, MgO: 0.59-4.85 %, Fe2O3: 0.68-1.82 % and (Na2O+K2O)/(CaO+MgO): 0.33-5.63. The chemical composition of zeolitized tuffs in the Demirci region is a function of selectivity of zeolite minerals additionally to the primary composition of the volcanism. Tuff samples containing high amounts of hul/cpt have higher values ​​for CaO, H2O, and most trace elements and REEs than the samples containing little or no zeolite. Key words: Clinoptilolite, Demirci, Geochemistry, Turkey, Zeolitization. https://doi.org/10.5194/egusphere-egu24-255
Flood Discharge Estimation in Ungauged Basins Using Synthetic Unit Hydrographs and GIS
No full textFlooding refers to the adverse effects caused by rivers overflowing their banks due to various reasons, affecting surrounding land, residential areas, and infrastructure. At the watershed scale, particularly in cases where flow monitoring stations are absent, hydrographs must be generated to analyze rainfall-runoff relationships for flood assessments. This study aims to generate synthetic hydrographs, analyze rainfall-runoff relationships, and estimate flood discharges for different return periods in a predominantly forested sub-watershed located in the Sarıyer district of Istanbul. The study analyzed extreme rainfall by calculating 24-hour maximum values for return periods of 2 to 100 years using four common probability distribution functions: Normal, Log-Normal, Log-Pearson Type III, and Gumbel. Among these methods, Log-Pearson Type III yielded higher rainfall values, and given the extreme nature of floods, it was preferred for discharge calculations. In the second stage of the study, flood hydrographs specific to the watershed were generated for different return periods using the DSI, Mockus, and Snyder unit hydrograph methods, incorporating watershed physical characteristics and dimensionless unit hydrograph coordinates. The results indicated that the DSI and Mockus methods produced similar and higher peak discharge values (Qₘₐₓ = 67.44 and 63.76 m³/s, T=100 years), whereas the Snyder method resulted in lower peak discharge (Qₘₐₓ = 32.17 m³/s for T = 100 years) but a longer hydrograph duration. Overall, it was concluded that the DSI and Mockus methods are more suitable for flood analysis in forested and relatively small watersheds (≈10 km²) due to their effectiveness in generating hydrographs for flood assessments. This study contributes to the literature by offering a comparative evaluation of three widely used synthetic unit hydrograph methods, specifically tailored for a forest-dominated ungauged basin in an urbanizing region of Istanbul, providing actionable insights for flood estimation in data-scarce, forested urban catchments.https://doi.org/10.62520/fujece.1645774https://dergipark.org.tr/tr/pub/fujece/issue/92842/164577
Production of chrome-manganese ligature using ferrosilicochrome dust as a reducing agent
No full textThis article presents the results of thermodynamic modeling of the process of obtaining chromium-manganese ligature from ferro-manganese ore and dust from crushing ferrosilicochrome (FeSiCr). The calculations were performed using the “HSC Chemistry” software package, where dust from crushing FeSiCr was used as a reducing agent. The analysis was performed by varying the reducing agent dust FeSiCr from 10 to 100 kg in increments of 10 kg per 100 kg of ferro-manganese ore, at temperatures of 1400°C, 1600°C and 1800°C. The mechanism of combined metallothermic reduction of chromium (Cr), manganese (Mn), and iron (Fe) was studied in a multicomponent Fe-Cr-Mn-Si-Al-Ca-Mg-O system. Based on thermodynamic data, it was found that the optimal consumption of reducing agent is 50 kg per 100 kg of ore, and the most effective melting temperature is 1600 °C, at which the best yield of chromium-manganese ligature is achieved. Additionally, laboratory tests were conducted under specific conditions, resulting in experimental samples of the ligature with the following chemical composition, %: Fe – 28.39, Cr – 16.58, Mn – 32.55, Si – 3.56.https://doi.org/10.36547/ams.31.3.222
Modeling a Mixed-Mode Cooling System with Correlation to Operable Building Facade Openings: Mathematical Logic Integration of Computational Fluid Dynamics and Energy Models
No full texthttps://doi.org/10.1061/jcemd4.coeng-1570
Artificial intelligence-assisted capsule endoscopy for detecting lesions in Crohn’s disease: a systematic review and meta-analysis
No full textBackground and objectivesCrohn’s disease (CD), a complex member of the inflammatory bowel disease spectrum, is characterized by the diversity and skipping distribution of intestinal mucosal lesions, significantly complicating its differential diagnosis with intestinal diseases such as ulcerative colitis and intestinal tuberculosis. With the increasing application of artificial intelligence (AI) in the medical field, its utilization in primary diagnosis has become more widespread. However, there is a lack of systematic evaluation regarding the specific efficacy of AI in identifying CD through capsule endoscopy.MethodsThis study conducted a comprehensive search of PubMed databases, Cochrane, EMBASE, and Web of Science up to May 21, 2024, to collect relevant literature. The Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool was used to rigorously assess the quality of included studies, and detailed information on study characteristics and AI algorithms was extracted. A bivariate mixed-effects model was employed to synthesize and analyze the sensitivity, specificity, and area under the receiver operating characteristic curve (AUC). Additionally, meta-regression and subgroup analyses were conducted to delve into the potential sources of heterogeneity.ResultsUltimately, eight studies encompassing 11 distinct AI models were included in this meta-analysis. The overall area under the curve (AUC) for AI in identifying CD through capsule endoscopy was 99% (95% CI, 100%-0.00), indicating high diagnostic accuracy. Specifically, the pooled sensitivity was 94% (95% CI, 93–96%), specificity was 97% (95% CI, 95–98%), positive likelihood ratio (PLR) was 32.7 (95% CI, 19.9–53.6), negative likelihood ratio (NLR) was 6% (95% CI, 4–7%), and diagnostic odds ratio (DOR) reached 576 (95% CI, 295–1,127). Meta-regression analysis further revealed that AI algorithm type, study population size, and study design might be key sources of heterogeneity.ConclusionThis study demonstrates the significant potential of AI technology in assisting endoscopists in detecting and identifying CD patients through capsule endoscopy. However, given the limitations and heterogeneity of current research, more high-quality, large-sample studies are needed to comprehensively and thoroughly evaluate the practical application value of AI in CD diagnosis, thereby promoting its widespread adoption and optimization in clinical practice.https://doi.org/10.3389/frai.2025.1531362https://pubmed.ncbi.nlm.nih.gov/40235858http://dx.doi.org/10.3389/frai.2025.1531362https://doaj.org/article/3971dbfee0494dc8a07c8912ac26190
Cultural Practice for Sustainability: Narratives from Zero Waste Life Series by NHK World
No full texthttps://doi.org/10.1007/978-981-97-9076-0_
Long-term perspectives on land-use changes and air pollution policies in Iran: A comparative analysis of regional and global patterns in atmospheric PM2.5
No full textFine particulate matter (PM2.5) pollution is a major environmental challenge across the Middle East, including Iran. However, a substantial lack of knowledge exists regarding the linkage between aerosol trends, specific compounds, and their interrelation with emissions, mitigation strategies, and land changes. This research comprehensively evaluates the spatiotemporal trends of PM2.5 and its main precursors (SO2 and BC) concentrations in relation to LULC (Land-Use and Land-Cover) changes and mitigation policies in Iran during 1980-2023. Surface PM2.5 concentrations were estimated using five monthly MERRA-2 simulation datasets, including sea salt2.5, dust2.5, BC, OC, and SO4. The Evaluation of MERRA-2 PM2.5 against ground-based measurements confirmed that the MERRA-2 reanalysis data is ideal for monitoring PM2.5 patterns in Iran. Our trend analysis showed that dust dominates high PM2.5 concentrations in southwestern and southeastern Iran during summer, while anthropogenic aerosols (SO2 and BC) are the most significant contributors to PM2.5 in urban areas like Tehran in winter. Overall, a significant rise in aerosol occurred over Iran during 1980-2023, which reversed to a decreasing trend in PM2.5, BC and SO2 around 2006-2010. At the regional scale, aerosols variations were influenced by land-use changes, while urban and agricultural LULC changes being the primary contributors in dust-dominant regions, accounting for 38.1% and 26.4% of the variation, respectively. Our findings indicate that, although land-use changes initially influenced air pollution trends, recent clean-air policies have been essential in reducing emissions across major urban centers. Additionally, these trends in Iran align with or diverge from global patterns, reflecting the rise in industrial emissions across South Asia and contrasting with policy-driven decreases in developed regions such as Europe and North America, highlighting the urgent need for effective policies and land management to mitigate urban air pollution from diverse aerosol sources.https://doi.org/10.1016/j.jenvman.2025.124346https://pubmed.ncbi.nlm.nih.gov/3989225
Scattering by a Dielectric Circular Cylinder in a Planar Layered Medium with MAS, MMP and T-Matrix Methods
No full texthttps://doi.org/10.1109/diped66951.2025.1119458