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Comparison of bacteria-based autonomous and autogenous healing performances of geopolymer mortar exposed to sulfate attack
No full textIn this study, the performances of bacteria-based autogenous and autonomous healing of metakaolin, red mud, and colemanite-based geopolymer mortar exposed to sulfate attack were compared. The red mud and colemanite in geopolymer mortar mixtures were used at 0%, 6%, and 4% of metakaolin by weight. Bacteria-free samples for autonomous healing and bacteria-containing samples for autogenous healing were produced. S. pasteurii was used as the bacteria in this study. Then, these specimens were exposed to sulfate attack for periods of 1, 2, 3, 6, and 12 months. After the samples were exposed to sulfate attack, the autogenous and autonomous healing process was carried out. In the healing process, a solution containing 9 × 108 cells/ml bacteria (Bac-media) was injected into the cracks with a syringe to heal the geopolymer mortar samples. The mass change, length change, compressive strength, ultrasonic pulse velocity, flexural strength, and capillary water absorption tests of autonomous and autogenous healing geopolymer mortar samples were performed. Also, SEM/EDS, FTIR, Micro-computed tomography (Micro CT), and XRD were carried out for microstructure analysis. This study found that the mechanical properties of autonomous healing samples were higher than those of autogenous healing samples. Also, Micro-CT analysis found that 98.51% of the total porosity of the geopolymer mortar exposed to the sulfate attack was filled with CaCO3 precipitated by using S. pasteurii. These results provide an effective method for the recovery of geopolymer composites subjected to durability effects such as sulfate attack
A Hybrid IVFF-AHP and Deep Reinforcement Learning Framework for an ATM Location and Routing Problem
No full textThe impact of alternative distribution channels, such as bank Automated TellerMachines (ATMs), on the financial industry is growing due to technological advancements.Investing in ideal locations is critical for new ATM companies. Due to the many factorsto be evaluated, this study addresses the problem of determining the best location forATMs to be deployed in Istanbul districts by utilizing the multi-criteria decision-makingframework. Furthermore, the advantages of fuzzy logic are used to convert expert opinionsinto mathematical expressions and incorporate them into decision-making processes. Forthe first time in the literature, a model has been proposed for ATM location selection,integrating clustering and the interval-valued Fermatean fuzzy analytic hierarchy process(IVFF-AHP). With the proposed methodology, the districts of Istanbul are first clustered tofind the risky ones. Then, the most suitable alternative location in this district is determinedusing IVFF-AHP. After deciding the ATM locations with IVFF-AHP, in the last step, aDouble Deep Q-Network Reinforcement Learning model is used to optimize the Cash inTransit (CIT) vehicle route. The study results reveal that the proposed approach providesstable, efficient, and adaptive routing for real-world CIT operations.</p
A robust three-dimensional Fermatean fuzzy approach for comprehensive strategy selection for photovoltaic energy development
No full textThe increasing global demand for sustainable energy has heightened the need for efficient strategies in photovoltaic (PV) energy deployment, particularly in developing regions. However, policy and market challenges necessitate robust decision-making frameworks for selecting the most effective strategies. This study presents a robust three-dimensional Fermatean fuzzy approach, integrating Strengths, Weaknesses, Opportunities, and Threats (SWOT) analysis, Stepwise Weight Assessment Ratio Analysis (SWARA), CRiteria Importance Through Intercriteria Correlation (CRITIC), and Evaluation Based on Distance from Average Solution (EDAS) under a Fermatean fuzzy (FF) environment. Methodologically, four alternative strategies are prioritized using sixteen SWOT-based criteria, identified through expert consultation and literature review. FF-SWARA and FF-CRITIC are employed for subjective and objective criteria weighting, respectively, and FF-EDAS is used for strategy ranking. Regarding the findings, “removal of fuel subsidy and its ramification” is identified as the most influential factor (weight: 0.0924), followed by “limited awareness and information dissemination” (0.0826), “weak institutional capacity” (0.0792), “energy security” (0.0701), and “limited access to funding” (0.0671). Among the strategies, “promoting public awareness of solar energy potential and market prospects” achieves the highest performance score (0.500), ranking as the most effective option. Sensitivity analysis confirms the robustness of the rankings under various weighting scenarios. These findings offer valuable insights and practical guidance for policymakers and stakeholders, supporting the development of targeted and sustainable PV energy strategies in the region
Disturbance Rejection Based Current Control for Permanent Magnet Synchronous Motor Drives Using a Discrete-Time Adaptive Controller With Periodic Estimation
No full textIn this paper, a non-linear adaptive direct current controller based on periodic estimation is proposed to significantly minimize the periodic torque ripples for the permanent-magnet synchronous motor system in the discrete-time setting. The discrete-time adaptive controller is designed to track the desired motor currents of motor and provide periodic disturbance rejection by constructing the estimation algorithm based on the digital processing of unknown periodic signals in each consecutive motor period, which requires only knowledge of periodicity. The asymptotic stability of the closed-loop system dynamics is proven through the convergence of current errors to zero as the period of the motor shaft approaches infinity. To test the robustness against periodic uncertainties and disturbances varying with the rotor displacement and to demonstrate the achievement of the desired steady-state response for stator current quality, detailed simulation experiments are carried out with comparisons to the classical deadbeat controller
Proton emission in ultraperipheral Pb-Pb collisions at sNN =5.02 TeV
No full textThe first measurements of proton emission accompanied by neutron emission in the electromagnetic dissociation (EMD) of Pb208 nuclei in the ALICE experiment at the Large Hadron Collider are presented. The EMD protons and neutrons emitted at very forward rapidities are detected by the proton and neutron zero degree calorimeters of the ALICE experiment. The emission cross sections of zero, one, two, and three protons accompanied by at least one neutron were measured in ultraperipheral Pb208-Pb208 collisions at a center-of-mass energy per nucleon pair sNN=5.02TeV. The 0p and 3p cross sections are described by the RELDIS model within their measurement uncertainties, while the 1p and 2p cross sections are underestimated by the model by 17-25%. According to this model, these 0p, 1p, 2p, and 3p cross sections are associated, respectively, with the production of various isotopes of Pb, Tl, Hg, and Au in the EMD of Pb208. The cross sections of the emission of a single proton accompanied by the emission of one, two, or three neutrons in EMD were also measured. The data are significantly overestimated by the RELDIS model, which predicts that the (1p,1n), (1p,2n), and (1p,3n) cross sections are very similar to the cross sections for the production of the thallium isotopes Tl206,205,204
Experimental Energy and Exergy Assessments of a Mechanical Vapor Compression Refrigeration System having Low-GWP Alternative Gas of Pure R1234yf and its Nanoparticle Mixtures using Artificial Intelligence Models
No full textMeasuring the effect of receptive and productive vocabulary size on foreign language skills
No full textVocabulary knowledge is crucial for developing English language skills, and assessing students' vocabulary levels offers an effective means to monitor their language development and predict their test performance. Therefore, this study examined the relationship between receptive and productive vocabulary knowledge and English language skills (reading, writing, listening, speaking, and use of English) of 306 Turkish university students enrolled in A1, A2, and B1-level EFL classes as part of a preparatory language program. Vocabulary knowledge was measured using a receptive and a productive vocabulary levels test, while language skills were assessed through an English Proficiency Exam and a speaking exam. The results revealed significant positive correlations between receptive and productive vocabulary knowledge, particularly at higher proficiency levels. Receptive vocabulary was found to be a much stronger predictor of language skills, especially for reading, listening, and use of English (UoE), than productive vocabulary which predicted performance in UoE. The impact of both vocabulary tests was more pronounced at higher proficiency levels, although their overall influence on language skills was limited. These findings suggest a nuanced relationship between vocabulary and language proficiency, while highlighting the need for systematic and balanced L2 instruction that includes different dimensions of vocabulary knowledge
Urban regeneration in response to natural disasters: Insights from the 2023 Kahramanmaraş earthquakes
No full textUrban regeneration has been promoted as a key strategy for disaster risk reduction, yet its effectiveness during major natural disasters remains under-evaluated. This study addresses the central problem of assessing whether urban regeneration implementations in designated at-risk areas effectively mitigated the impacts of the 2023 Kahramanmaraş Earthquakes in Türkiye. Despite extensive urban regeneration policies under Disaster Law No. 6306, there is a notable gap in empirical research evaluating their real-world performance during significant seismic events. To fill this gap, we conducted an empirical analysis of 12 at-risk areas across 11 provinces affected by the earthquakes. Utilizing satellite imagery, regional damage proxy maps, and spatial data analysis with ArcGIS Pro, we compared pre- and post-earthquake conditions to analyze the resilience of these areas. Our results reveal a dichotomy: regenerated at-risk areas (#5, #7, #11, #12) exhibited significantly lower damage, indicating enhanced physical resilience through effective interventions. In contrast, some non-regenerated at-risk areas (#1, #9) suffered severe damage, highlighting vulnerabilities due to delayed implementations. On the other hand, other non-regenerated at-risk areas (#2, #3, #4, #6, #8, #10) experienced minimal damage, suggesting misalignment between designated risks and actual vulnerabilities. Key findings underscore the necessity for accelerating urban regeneration processes and conducting detailed risk assessments to accurately designate at-risk areas. Practical implications include policy recommendations for refining legal frameworks, establishing clear scientific standards for risk evaluation, and promoting genuine citizen participation to enhance urban resilience. This study provides novel empirical evidence on the effectiveness of urban regeneration in disaster mitigation, offering valuable insights for policymakers and urban planners aiming to strengthen the resilience of urban environments against future natural disasters
Eco-friendly fabrication of bioactive chitosan-hydroxyapatite sponge-like scaffolds functionalized with Ficus carica Linn leaf extract for enhanced antioxidant and antimicrobial properties
No full textConquérir par le Geist. Carl Heinrich Becker, un islamologue au service de la politique orientale allemande
No full textConquérir par le Geist. Carl Heinrich Becker, un islamologue au service de la politique orientale allemandeAbstract This article examines the links between the “oriental policy” (Orientpolitik) implemented by the Kaiserreich and the emergence of Islamic studies as an institutionalised body of knowledge on Islam, no longer viewed solely as a religion, but as a cultural area and an identity building factor. Based on an analysis of Carl Heinrich Becker’s writings on Ottoman Turkey and the modernisation of Islam, the article shows how this reconfiguration of knowledge gave rise to a new type of orientalism, placed at the service of Germany’s “Muslim policy” (Islampolitik) and overall strategy to compete with the European colonial powers in the late Ottoman Empire. This strategy, which culminated in the First World War, was based on anti-colonial rhetoric, aimed at strengthening Turkish nationalism and undermining the French cultural and linguistic hegemony nurtured by the Ottoman elites.Résumé Cet article interroge les liens entre la « politique orientale » (Orientpolitik) mise en oeuvre par le Kaiserreich et l’émergence des études islamiques comme un ensemble institutionalisé de savoirs sur l’Islam, envisagé non pas uniquement comme religion, mais comme aire culturelle et facteur identitaire. À partir d’une analyse des écrits de Carl Heinrich Becker sur la Turquie ottomane et la modernisation de l’Islam, l’article montre comment cette reconfiguration des savoirs a donné naissance à un orientalisme de type nouveau, mis au service d’une « politique musulmane » (Islampolitik) et d’une stratégie globale de l’Allemagne pour concurrencer les puissances coloniales européennes dans l’Empire ottoman finissant. Cette stratégie, qui culmina pendant la Première Guerre mondiale, mobilisa une rhétorique anticoloniale, visant à renforcer un nationalisme turc et saper l’hégémonie culturelle et linguistique française entretenue par les élites ottomanes.<br