Istanbul Technical University
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Adaptive locally connected recurrent unit (ALCRU)
No full textAbstract Research has shown that adaptive locally connected neurons outperform their fully connected (dense) counterparts, motivating this study on the development of the Adaptive Locally Connected Recurrent Unit (ALCRU). ALCRU modifies the Simple Recurrent Neuron Model (SimpleRNN) by incorporating spatial coordinate spaces for input and hidden state vectors, facilitating the learning of parametric local receptive fields. These modifications add four trainable parameters per neuron, resulting in a minor increase in computational complexity. ALCRU is implemented using standard frameworks and trained with back-propagation-based optimizers. We evaluate the performance of ALCRU using diverse benchmark datasets, including IMDb for sentiment analysis, AdditionRNN for sequence modelling, and the Weather dataset for time-series forecasting. Results show that ALCRU achieves accuracy and loss metrics comparable to GRU and LSTM while consistently outperforming SimpleRNN. In particular, experiments with longer sequence lengths on AdditionRNN and increased input dimensions on IMDb highlight ALCRU’s superior scalability and efficiency in processing complex data sequences. In terms of computational efficiency, ALCRU demonstrates a considerable speed advantage over gated models like LSTM and GRU, though it is slower than SimpleRNN. These findings suggest that adaptive local connectivity enhances both the accuracy and efficiency of recurrent neural networks, offering a promising alternative to standard architectures.https://doi.org/10.1007/s13042-025-02652-
Epoxy-Functional (Alkyl)methacrylate-Based Hybrids Reinforced with Layered Silicate Montmorillonite: From Mechanistic Study to Sustainable Wastewater Treatment
No full textThis work aims to design versatile hybrids fabricated by poly(hydroxypropyl methacrylate-co-glycidyl methacrylate) gels loaded with pristine montmorillonite, P(HPMA-co-GMA)/Mmt, by varying the clay content. Insights into design of epoxy-functional hybrids were provided by combining in situ copolymerization reactions with solution mixing to evaluate the effect of aluminosilicate addition on structure–property changes in (alkyl)methacrylate-based gels. Comprehensive analyses were conducted regarding the composition and structural properties of hybrids in the presence of Mmt. The hybrids exhibited excellent swelling, salt surfactant tolerance, and pH sensitivity depending on the composition. The higher the Mmt concentration, the lower the swelling ratio; however, the compressive moduli did not change monotonically with increasing Mmt from 0.80 to 2.20% (w/v). Dye adsorption revealed the effects of variables (dye type, pH, contact time, concentration) on adsorptive properties of hybrids towards cationic methylene blue (MB) and anionic sunset yellow, allura red, blue brilliant, carmoisine, and tartrazine dyes. Adsorption kinetics of MB obeyed pseudo-second-order model, and the maximum dye adsorption capacity for hybrids increased from 5.01 mg g−1 to 16.42 mg g−1, while adsorption isotherms were defined by the Freundlich model. The proposed hybrids have emerged as alternative materials that enable multiple uses of same adsorbent for the removal of different types of pollutants.https://doi.org/10.3390/gels11100803https://pubmed.ncbi.nlm.nih.gov/41149408/https://pmc.ncbi.nlm.nih.gov/articles/PMC12562478
Lean Office System Design: An Application from the Banking Industry
No full texthttps://doi.org/10.1007/978-3-031-88071-1_2
Nature-Life Fusion Through Deleuzian-Guattarian Posthumanism
No full textThis article aims to analyze a theoretical reconceptualization of the materiality of nature. To this end, this study raises two political problems of nature, specifically as a concept. The first problem is the modern concept of nature, which depicts its materiality as a mechanical concept, resulting in the domination of nature. On the other hand, the second problem is the postmodern concept of nature, which presents its materiality as a function of discourse. In this respect, there is no nature; it is political. This article presents an antidote derived from a critical posthumanist perspective based on the works of Deleuze and Guattari, Capitalism and Schizophrenia. In this context, I advocate a new materiality of nature that constitutes an ethics of immanence and sees nature as a process of life production from the posthumanist approach. Nature is a plane where all life emerges, representing a dynamic production process.https://doi.org/10.53376/ap.2025.0
A Comparative Study on Multi-Fidelity Machine Learning Modeling for Aerospace Problems
No full texthttps://doi.org/10.2514/6.2025-027
Correction: Median-Linear model for solar radiation estimation by comparison with ANFIS and Angström-Prescott methods
No full texthttps://doi.org/10.1007/s40808-025-02614-
A BIM-Based Multi-Criteria Spatial Framework for Assessing Fire Risks in Indoor Environments
No full textBuilding fires are considered major disasters because of their significant effects on people, property, and the environment. This understanding has led to increased attention on developing preventive measures, particularly through the creation of effective methods for assessing fire risk. However, the effectiveness of these methods relies heavily on detailed physical and functional information of the building and data-driven decision-making. Building Information Modeling (BIM) has proven effective in representing structures, even in three dimensions. When integrated with Geographic Information Systems (GIS), it enhances spatial intelligence, leading to improved decision-making through robust multi-criteria approaches. Hence, this study develops a framework to assess fire risk in an indoor environment that deploys a BIM-based GIS and Multi-Criteria Decision-Making; this is specifically known as Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). The developed framework consists of four steps: identifying fire risk parameters, calculating weights, conducting spatial fire risk assessments, and visualizing the results, where the developed concepts are tested and validated. According to the significant findings, the developed framework estimates that 18% of building rooms are at moderate risk, while the compared model identifies only 1%. This considerable difference could potentially arise from the detailed data structure of BIM and the spatial insights gained from GIS. By implementing the designed framework, key fire risk factors can be identified in three dimensions, accompanied by a comprehensive quantitative evaluation platform for fire risks within indoor environments.https://doi.org/10.3390/fire809036
Correlations Between Textural Properties of Potato Chips and Diffusion Coefficients of Frying Oils
No full textABSTRACT In this study, potato slices were fried in four different vegetable oils (corn, olive, palm olein, and sunflower) to investigate how oil type influences the characteristics of potato chips. The diffusion coefficient of oils was attempted to be correlated with the final moisture, oil uptake, and textural parameters of potato chips. The diffusion coefficients were determined using two approaches. First, they were experimentally measured in a model matrix using dynamic light scattering (DLS) at 60°C, 70°C, and 80°C and subsequently extrapolated to the frying temperature (180°C) using the Arrhenius equation. Second, the effective diffusion coefficients were calculated based on Fick's law of diffusion. All chips were fried to a low moisture content (~1%–2%), but fat contents ranged widely from about 32% to 43% depending on the oil used. Chips fried in the highly saturated palm olein absorbed the least oil (~32%) and had the highest hardness (peak force), whereas those fried in polyunsaturated sunflower oil had the highest oil content (~43%) and lowest hardness. Diffusion coefficient measurements in the model system also differed by oil type (e.g., sunflower oil showed the lowest molecular diffusion rate), although the calculated effective diffusion coefficients of oils into chips were of similar order (~10 −6 m 2 /s) for all oils. The correlation analyses revealed strong correlations between oil diffusion coefficients and chip moisture, fat content, and texture, highlighting the role of oil mobility in determining product quality. Understanding these correlations can help optimize frying processes and oil selection to produce chips with lower oil content and desirable crispness.https://doi.org/10.1111/jtxs.7003
Damping capability enhancement of the polyurethane seismic isolation device for HV post insulators and its numerical evaluation with the 2023 Kahramanmaraş, Türkiye Earthquake Sequence
No full textOne of the most effective methods of improving high-voltage (HV) porcelain insulator earthquake performance is seismic isolation. A low-cost seismic isolation device consisting of polyurethane springs has been developed previously to ensure the seismic safety of porcelain insulators. In this study, a supplementary steel damper mechanism was designed to improve the damping properties of the device. Quasi-static tests were conducted to determine the contribution of the proposed mechanism to the system characteristics, such as additional stiffness and damping. An extensive shaking table test program was carried out on a post-insulator system with and without base isolation to investigate the global dynamic behavior of the system while subjected to seismic excitation. Ten historical earthquake records matched with the required response spectrum of IEEE693-2018 were applied, and the experimental results were used to validate the finite element model. The effects of the proposed damping mechanism on the seismic isolation system were investigated experimentally and numerically. The effectiveness of the seismic isolation device with additional damping mechanisms has been assessed for a case study of the 6 February 2023 Kahramanmaraş (Pazarcık M7.7 and Elbistan M7.6) Earthquakes.https://doi.org/10.1177/87552930251315437https://doi.org/https://doi.org/10.1177/8755293025131543
Textile‐based Low‐frequency RC Filter for Noise Reduction in ECG signals
No full textAbstractAdvancements in electronic textiles over the past decade have significantly transformed the field of wearable technology, with recent developments leading to the production of a wide array of textile‐based sensing and actuation systems. Beyond sensors and actuators, textile‐based technologies can benefit from the integration of additional electronic solutions within the framework of textilization. One such solution is filtering, which has primarily been explored in the context of high‐frequency applications in e‐textiles. In contrast, low‐frequency filtering has received limited attention in the literature. This study investigates the design and fabrication of low‐frequency textile‐based Resistor–Capacitor (RC) filters, emphasizing their potential for wearability. Various materials and geometric configurations are explored for the resistive and capacitive components of the filter, evaluating their performance in terms of frequency response. Additionally, these filters are integrated with textile‐based electrodes and assess their filtering efficacy at a cutoff frequency of approximately 100 Hz within the context of an electrocardiogram (ECG) application during both static and dynamic activities. The results demonstrate that textile‐based filters can serve as viable alternatives to conventional electronic filters, exhibiting comparable performance in noise suppression, as evidenced by signal‐to‐noise ratio (SNR) improvements of 25 dB during static activities and 11 dB during dynamic activities.https://doi.org/10.1002/gch2.202400237https://pubmed.ncbi.nlm.nih.gov/40071226http://dx.doi.org/10.1002/gch2.202400237https://doaj.org/article/8d5362c006f44b2e90c8b1e5b7fc046