Istanbul Technical University
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Investigation of Attitude-Independent Magnetometer Calibration Approaches Under Various Conditions
No full texthttps://doi.org/10.1109/metroaerospace64938.2025.1111468
xApp-based Resource Allocation for Network Slices in End-to-End 5G System
No full texthttps://doi.org/10.1109/siu66497.2025.1111234
Comprehensive experiences on the operation of a full-scale continuous dry anaerobic digestion plant treating mechanically sorted OFMSW
No full textABSTRACT Anaerobic digestion (AD) of the organic fraction of municipal solid waste (OFMSW) is a crucial waste management method for the diversion of organics from landfills to decrease greenhouse gas emissions while enabling energy recovery. A number of dry AD systems treating OFMSW have notably increased over the last two decades. In this study, mono-digestion of mechanically sorted OFMSW and co-digestion of OFMSW, chicken manure and WWTP sludge were evaluated using triplicate full-scale digesters. Results demonstrated that 5–6.6 m3biogas/m3reactor.day biogas could be produced at an organic loading rate (OLR) of 10.5–12 kg TVS/m3.day, with an HRT of 16–18 days. Beyond this threshold, further increases in OLR resulted in reduced gas production due to ammonia inhibition as a result of broiler chicken manure overload. Biogas yield decline started when the chicken manure content of the feed was increased to 10% (w/w) and accompanied with the VFA/TA ratio rising above 0.8. Process instability and a sharp drop in biogas productivity were observed when the feed contained more than 20% (w/w) chicken manure, where VFA/TA ratio exceeded 1.0. Results underline the importance of balancing different properties (e.g., degradability, carbon to nitrogen (C/N) ratio) of co-substrates to optimize the biogas yield and to ensure process stability.https://doi.org/10.2166/wst.2025.06
<b>Evaluation of English Language Teaching via Objective-Based Curriculum Evaluation Model</b>
No full textThis study explores the effectiveness of a curriculum designed to teach the Simple Past Tense to high school preparatory students within a communicative and student-centered framework. The participants were 24 male students, aged between 14 and 15, all possessing A2-level English proficiency. Through a combination of pre- and post-tests, the study assessed progress in students’ core language skills: speaking, listening, reading, and writing. Additionally, both teacher and student observation forms were employed to examine classroom engagement and instructional impact. For one week, the lessons emphasized real-life application of the past tense, aiming to create meaningful and interactive learning experiences. Quantitative data were analyzed using dependent samples t-tests to identify any significant improvements in language performance. Complementary to this, qualitative data from observation forms were subjected to thematic analysis to uncover patterns related to participation and instructional effectiveness. Findings suggest that integrating grammar instruction with real-world tasks enhances student engagement and reinforces learning outcomes. The study highlights the importance of balancing form-focused instruction with communicative practices and offers implications for refining grammar teaching strategies in similar contexts.https://doi.org/10.46328/ijres.132
The overlooked conservation value and ecosystem services of saline lakes
No full text<title>Abstract</title> <p>Saline lakes are hypersensitive to changes in their water balance and therefore show amplified responses to climatic and land-use changes in their catchment. However, despite the resulting, often dramatic ecological consequences, saline lakes rank low on policy agendas as they are assumed to support few ecosystem services and low levels of biodiversity. Here, we challenge this view and evaluate ecosystem services and threatened species in 84 saline lakes distributed across the globe. We found that saline lakes harbour not only threatened aquatic biota but also a diverse range of red-listed terrestrial species that critically rely on the lakes’ existence. Further, our results highlight that saline lakes support, irrespective of their salinity, a number of culturally and economically important ecosystem services. We conclude our analysis with best-practice recommendations for sustainable management of saline lakes. Their local adaptation and implementation will be key for safeguarding biodiversity and ecosystem services of these valuable but highly sensitive ecosystems.</p>https://doi.org/10.21203/rs.3.rs-5835171/v
A Study on Power System Retrofit for Cessna-172S Aircraft by Using Hydrogen Fuel Cell and Battery Hybrid
No full textThe electrification of aviation is predominantly driven by environmental concerns associated with emissions. In this context, while the More Electric Aircraft and Hybrid Electric Aircraft concepts are currently at the forefront, the long-term objective is the utilization of All Electric Aircraft. Presently, the transition to All Electric Aircraft, which includes the electrified propulsion system, seems challenging due to the significant energy and power demands of aircrafts, given that the specific energy of recent energy storage technologies and power density of other electrical parts are not at the desired levels. Nevertheless, various scientific findings are being explored to accelerate this process and fuel cells are emerging as a solution. This study examines the retrofitting of a Cessna 172S, selected as the baseline aircraft, into a fully electric version with a hybrid configuration combining a battery and fuel cell. The modification process includes the development of an electrical power system architecture, selection of the required components, and modeling of the system elements. The new configuration of the platform is investigated through various simulations to evaluate the impacts on power sharing of the battery and fuel cell, and a comparative weight analysis is conducted between the baseline and retrofitted aircraft. The study concludes with a critical examination of the benefits and challenges related to the All Electric Aircraft concept.https://doi.org/10.1109/access.2025.3526633https://doi.org/10.1109/ACCESS.2025.3526633https://doaj.org/article/4ac77c91f7894f3a92cafbf9e8a29e8
Development of PLA‐Based Composite Nanofibers Incorporating Tricalcium Phosphate and Graphene Oxide for Bone Tissue Engineering
No full textAbstract Bone tissue engineering has emerged as a promising approach for aiming to repair the damaged tissue using biomaterials. In this study, composite polylactic acid (PLA) matrices were produced via electrospinning incorporating 2 wt% tricalcium phosphate (TCP) and varying concentrations of graphene oxide (GO) (0.4, 0.8, and 1.2 wt%). The morphological properties and chemical compositions were analyzed using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR), respectively. Differential scanning calorimetry (DSC) was employed to study the thermal properties of the nanofibers. Swelling and degradation behaviors were assessed, along with GO release kinetics. Overall, the novelty of this work lies in the optimized integration of GO, particularly at 0.4 wt%, which provides enhanced mechanical properties and superior biocompatibility. This composition exhibited enhanced swelling capacity and the lowest degradation rate over 30 days, supporting structural integrity and scaffold stability. GO release from the nanofibers followed a sustained and controlled profile, minimizing initial burst effects. Notably, PLA/TCP/0.4 GO achieved the highest hFOB cell viability on days 3 and 7. Collectively, these results identify 0.4 wt% GO as the optimal concentration, offering a well‐balanced combination of mechanical robustness, degradation resistance, and biological performance for bone tissue engineering applications.https://doi.org/10.1002/slct.20250240
Teachers' Emotion Regulation in the Workplace: A Comparative Systematic Review
No full textABSTRACT This research aims to explore and compare descriptive context‐specific characteristics and workplace outcomes of the studies on teachers' emotion regulation (TER) at primary education (PE) and secondary education (SE) levels. A systematic review with a mapping approach was employed on NVivo 14 to provide a thorough overview of TER studies in the literature indexed in the Web of Science at PE and SE levels. Accordingly, 20 TER studies in PE and 31 in SE were identified to be reviewed systematically. Descriptive findings suggested a rise in TER studies. Quantitative methods were dominantly employed, and the majority were conducted in China. The conceptual focus of the studies highlighted two key areas: emotion regulation and emotional labour. The primary research focus was found to be affective factors in the workplace. The findings of conceptual analyses on the workplace outcomes revealed five themes at both levels, namely, leadership and management, organisational climate and support, cultural and diversity considerations, teacher development, and classroom and interaction dynamics consisting of similar and distinctive codes.https://doi.org/10.1111/ejed.7006
Effect of solution-blown polyamide-6 nanofiber interlayer on drilling performance of carbon fiber reinforced composites
No full textThis study examines the effect of solution-blown polyamide-6 (PA6) nanofiber interlayers on the drilling performance of carbon fiber reinforced polymer (CFRP) composites. Results demonstrate that PA6 nanofiber interlayers significantly reduce drilling thrust force and improve surface quality. Specifically, at a spindle speed of 1000 r/min and a feed rate of 1500 mm/min, the maximum thrust force was reduced by 17%, from 683.33 N in neat composites to 583.13 N in nanofiber-reinforced composites. At a higher spindle speed of 8000 r/min and a feed rate of 500 mm/min, thrust force decreased by 18%, from 80.22 N to 65.46 N. Surface roughness analysis revealed that nanofiber interlayers reduced Ra values by up to 44%, with a minimum roughness of 0.529 µm compared to 1.196 µm in neat composites. Optical and SEM analyses confirmed fewer plucking zones, reduced fiber pull-out, and improved fiber-matrix bonding in nanofiber-reinforced samples, particularly at higher spindle speeds. These findings indicate that PA6 nanofiber interlayers enhance drilling performance, offering reduced machining forces and superior hole quality for precision applications in the aerospace and automotive industries.https://doi.org/10.1177/0731684425131885
Splitter: Faster Inference through Channel Partitioning and Feature Fusion
No full texthttps://doi.org/10.1109/icip55913.2025.1108454