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A simulated annealing with graph-based search for the social-distancing problem in enclosed areas during pandemics
No full textDuring the pandemic, decision-makers offered many preventive policies to reduce the negative effects of the pandemic. The social distance rule in enclosed areas was implemented by educational institutions in any countries. In this study, we deal with the problem of assigning students to seats by considering the social distancing constraint and with objective of maximizing the total distance among the students. This problem is found to be similar to the Maximum Diversity Problem (MDP) in the literature. We name this new problem as Maximum Diversity Social Distancing problem (MDPs). A simulated annealing algorithm framework for MDPs (SA-MDPs) is proposed to identify an optimal or near-optimal solution within a reasonable computational time. A greedy random-based algorithm is presented to determine efficiently an initial feasible solution. The new neighborhood search procedure based on graph theory is introduced, in which the dominated, dominating, and nondominated seats are determined based on social distance. The proposed SA-MDPs is evaluated on classrooms with varying capacities and benchmarked against an off-the-shelf optimization solver. The computational tests demonstrated that the SA-MDP model consistently provided either proven optimal solutions or superior best-known solutions compared to a commercial solver, all within a reasonable CPU time
A Review on Latest Developments in Assembly and Temporary Shelters for Natural Disasters
No full textAssembly and temporary shelter areas are spaces that allow people to stay in safe zones following a disaster. Therefore, studies related to assembly areas and temporary shelters, particularly within the framework of natural disasters, are of great importance. This article examines the efforts concerning assembly areas, temporary shelters, and evacuations during a natural disaster process. The purpose of this review is to identify challenges, provide a research gap, and propose potential research directions for the future. The motivation behind this study stems from the increasing number of natural disasters in recent years due to climate change and the need for ideas to ensure the well-being of disaster victims and regional authorities. For the first time, this study reviews the literature on assembly areas and temporary shelters regarding natural disasters over the past three years. Finally, following the analysis of the reviewed studies, some potential options for future research are suggested. © 2025 Elsevier B.V., All rights reserved
Magnesium-doped Cobalt ferrites (Mg1-xCoxFe2O4) as high-performance catalysts for Hydrogen generation via NaBH4 methanolysis
No full textThis study explores the use of magnesium-doped cobalt nanoferrites, Mg1-xCoxFe2O4 (denoted as MgCoN, with x = 1, 0.75, 0.625, 0.375, 0.25, and 0), synthesized via the sol-gel auto-combustion method for hydrogen production through the methanolysis of sodium borohydride. The crystal structures were characterized using various techniques:XRD, SEM), EDS, VSM, FTIR, and Raman spectroscopy. The effect of various parameters including the molar ratios of Mg and Co in the MgCoN catalysts, amounts of methanol, NaBH4 and catalyst, and the temperature on the initial hydrogen generation rate (HGR) were investigated. The findings indicate that the Mg0.25Co0.75Fe2O4 catalyst exhibits remarkable efficiency, achieving an HGR of 56,695.2ml/min center dot gcat with a notably low activation energy of 13.67kJ/mol. These results highlight the potential of Mg0.25Co0.75Fe2O4 for large-scale hydrogen production applications. The structural and magnetic properties of the MgCoN were shown to significantly enhance catalytic efficiency, facilitating more effective interactions between reactants and catalytic sites during the methanolysis reaction.Directorate-General for Scientific Research and Technological Development (DG-RSDT)The authors thank the Directorate-General for Scientific Research and Technological Development (DG-RSDT) for financial support
Machine learning-based optimization and shap analysis of material, pressure, and fluid type effects on different outlet temperatures in a Ranque-Hilsch vortex tube
No full textNumerous studies have explored the complex dynamics and practical applications of vortex tubes (VT), with experimental approaches offering advantages in empirical validation and real-world data acquisition. In this study, a novel experimental setup was developed by connecting two counterflow vortex tubes in parallel to investigate the effects of key input parameters inlet pressure, nozzle type, and material on the hot outlet temperature (Th), cold outlet temperature (Tc), and temperature difference (Delta T). Unlike conventional methods, separate datasets were created for each output variable. Several machine learning regression models linear regression (LR), random forest (RF), K-nearest neighbors (KNNs), XGBoost (XGB), CatBoost (CatB), and gradient boosting (GB) were trained and compared to identify the most accurate predictors. SHAP (SHapley Additive exPlanations) was employed to interpret feature importance, and grid search optimization was used to fine-tune model parameters. Results showed that XGB achieved the highest accuracy (97%) for Tc, while CatB provided the best predictions for Th and Delta T, also at 97% accuracy. These findings demonstrate the efficacy of machine learning in modeling VT behavior and highlight the potential of the proposed setup for enhanced thermal performance analysis
Public Chaos: Alleged Fatwa on Boycotting and the Fear of Missing Out on Israeli Products in Indonesia
No full textThe following text presents a synopsis of the abstract. As the conflict between Israel and Palestine intensifies, the Indonesian Ulama Council (MUI) has issued a fatwa that has generated controversy in various mass media, particularly on social media platforms. The objective of this study is to examine whether the "fatwa" issued by the Indonesian Ulama Council (MUI) constitutes a legitimate threat against Israeli products or a misinterpretation of the fatwa within the community. The research method employed is qualitative, with a descriptive-analytical approach. The secondary data set comprises social media platforms, including Instagram, Twitter, and YouTube, as well as websites relevant to the author's research. The primary data was obtained through interviews with various stakeholders, including consumers, MUI members, pro-Palestinian activists, and digital communication experts. The results indicated that misinterpretations of the fatwa led to public disorder, characterized by ambiguity in public perception, social pressures encouraging boycott conformity, and exacerbated consumer confusion due to digital misinformation. This research highlights the importance of religious literacy and the need to establish information authority within the digital landscape. © 2025 Elsevier B.V., All rights reserved
Microstructure, dislocation and high-temperature oxidation behavior of as-cladding NiCoFeCrMo high-entropy alloy coatings: Laser cladding vs vacuum cladding
No full textNiCoFeCrMo high-entropy alloy (HEA) coatings were fabricated using laser cladding (LC) and vacuum cladding (VC), and their microstructures, dislocation characteristics, and high-temperature oxidation behavior at 600 degrees C were systematically compared. The LC coating exhibits a dendritic single-phase FCC solid solution, whereas the VC coating presents an FCC+ sigma eutectic structure. The former displays greater lattice distortion, higher dislocation density, lower screw density, and more stacking faults than the latter, resulting in superior hardness, plastic deformation resistance, and dynamic recrystallization. The oxidation rate constant (k) and oxidation rate of the LC coating are 1.4247 x 10- 3 and 2.19 x 10- 3 mg & sdot;cm- 2 & sdot;h- 1, while those of VC coating are 1.5633 x 10- 3 and 2.47 x 10- 3 mg & sdot;cm- 2 & sdot;h- 1, respectively, indicating that the LC coating exhibits better high-temperature oxidation resistance. The LC coating is covered by a double-layer oxide film composed solely of Cr2O3, whereas the VC coating develops a loose oxide layer containing Cr2O3 and (Cr,Fe)2O3. Due to its higher lattice stress, dislocation density, screw density, and stacking faults, the LC coating exhibits greater lattice distortion, high-temperature toughness, and plastic resistance compared to the VC coating. High-temperature oxidation behavior is influenced by element diffusion, oxygen permeation, oxide formation, and internal stress. The continuous formation of dense oxides and the inhibition of oxygen permeation provide the LC coating with excellent oxidation resistance. In contrast, the VC coating ' s elevated oxygen permeability, formation of loose oxides, and degradation of the sigma phase reduced its protective efficacy.National Natural Science Foundation of China [51605230, 52371033]; Key Research and Development and Promotion Special Project in Henan Province [232102221022]; Postgraduate Education Reform and Quality Improvement Project in Henan Province [YJS2025AL148]; Nanyang City Key Research and Development Special Program [24ZDYF015]; Nanyang City Basic and Frontier Technology Research Special Projects in Henan Province, China [23JCQY1001, 23JCQY2013]This work was financially supported by the National Natural Science Foundation of China (Nos. 51605230, 52371033) , the Key Research and Development and Promotion Special Project in Henan Province (No. 232102221022) , the Postgraduate Education Reform and Quality Improvement Project in Henan Province (No. YJS2025AL148) , the Nanyang City Key Research and Development Special Program (No. 24ZDYF015) , and the Nanyang City Basic and Frontier Technology Research Special Projects (Nos. 23JCQY1001 and 23JCQY2013) in Henan Province, China
Diversity, intersectionality, and the role of religion in intercultural relationships
No full text[No abstract available
Fertility Variation in Clonal Seed Orchards and Their Base Populations of Black Pine
No full textFertility variation and linkage parameters (i.e., effective population size, gene diversity) were estimated in three clonal seed orchards and their origins meant base population depending on strobilus production to contribute selection, establishment and management of seed sources in Anatolian black pine [Pinus nigra Arnold. subsp. pallasiana (Lamb.) Holmboe] for three consecutive years (2022, 2023 and 2024). The strobili productions of base populations were higher than their own seed orchards. Female and male strobili productions were significantly (p < 0.05) different among populations and years, and among clones within year according to results of analysis of variance. The gametic (female and male fertility variations) and zygotic/total fertility variations were acceptable level for the years and populations. Fertility variation among individuals were lower in good crop years than in poor year. Loss of gene diversity was less than 0.003 between base populations and their own seed orchards. Three years results of the study indicated that the strobili traits were reflected well to seed orchards by their base populations based on estimated fertility variation and linkage parameters.Scientific and Technological Research Council of Turkey (Tubitak) [221O178]The authors thank to Scientific and Technological Research Council of Turkey (Tubitak) for their financial support under the Grant no. 221O178. Authors also thank to The Research Directorate of Forest Tree Seeds and Tree Breeding of Turkey for the administrative support
Evaluation of phase change material-impregnated waste tire-derived carbon in cement-expanded vermiculite-based composites for solar thermoregulation of buildings
No full textThis study introduces an innovative phase change material (PCM) impregnated waste tire-derived carbon (WTC), based on the dire need for enhanced energy efficiency and building temperature management. Thermal energy storage materials were produced by combining capric acid (CA) and palmitic acid (PA) eutectic mixture (CA-PA) with WTC in cement-expanded vermiculite-based composites (CEVCs). The study comprehensively evaluates the impact of PCM-impregnated WTC on the thermoregulation performance of CEVCs in specially prepared test cabins under real weather conditions. Moreover, the material's physio-mechanical properties, thermal conductivity, thermal stability, and thermal behavior were also investigated, validating its ability to absorb and discharge latent heat. The results revealed that WTC/CA-PA experienced latent heat values of 85.2 J/g and 85.8 J/g during solidification and melting, respectively. Furthermore, it was observed that composites containing 10-40 % PCM-impregnated WTC exhibited 12.7-43.7 % and 25.5-160.8 % higher dry unit weight and compressive strength than the reference specimen. The solar thermoregulation experiments at real weather conditions revealed that CEVC containing PCM-impregnated WTC produced a maximum difference of 5.3 degrees C and 3.53 degrees C in temperature between the upper surfaces and near surfaces of the test and reference chambers. The promising results symbolize a significant shift toward fostering sustainable construction practices, encompassing occupant comfort and energy efficiency for a sustainable built environment while addressing the critical issue of waste tire recycling
Higher Education Learners' Perception of the Online Flipped Instruction
No full textBu nitel çalışma, İranlı yüksek öğretim öğrencilerinin çevrimiçi ters çevrilmiş öğretime ilişkin algılarını araştırmayı amaçladı. Katılımcılar İngilizce Çevirmenlik bölümünde okuyan 25 İranlı lisans öğrencisiydi. İran'da bir dönem boyunca 'Dil Öğretiminde Yaklaşımlar ve Yöntemler' başlıklı çevrimiçi bir kurs için ters çevrilmiş eğitim aldılar. Veriler yapılandırılmış bir görüşme yoluyla toplanmıştır. Tüm katılımcıların deneyimlerinden memnun oldukları belirlendi. 'Etkili öğrenme', 'ilginç ve motive edici ders', 'daha fazla etkileşim', 'daha fazla işbirliği ve ortak çalışma', 'daha fazla katılım', 'faydalı ders zamanı', 'takım çalışması öğrenme', 'kontrol' gibi çeşitli faydalar belirtildi. zamanında öğrenme', 'pratik bilgi ve beceriler edinme', 'stresi azaltma', 'kendini yansıtma ve kendini değerlendirme', 'sorumluluk almayı öğrenme', 'öz güveni artırma', 'sınıfta daha fazla dikkat', 'Etkili geri bildirim alma', 'özerk olma' ve 'tüm öğrenme stillerini karşılama'. Ancak beş öğrenci de yaklaşımın öğrencilere ağır bir yük getirdiğinden şikayetçi oldu. Altı öğrenci, zayıf internet bağlantısının ve yeterli teknolojik araçların bulunmamasının, ülkenin yoksul bölgelerinde eğitim gören öğrenciler için zorluk yaratabileceğini savundu. Bu nedenle, çevrimiçi ters çevrilmiş pedagoji yoluyla olumlu sonuçlar elde edilebilir, ancak dikkatli bir planlama da gereklidir.This qualitative study aimed at exploring the Iranian higher education learners' perception of the online flipped instruction. The participants were 25 Iranian undergraduates who were English Translation majors. They received the flipped instruction for an online course, entitled 'Approaches and Methods in Language Teaching' for a semester in Iran. The data were gathered by a structured interview. It was found that all the participants were satisfied with their experience. Several benefits were stated, such as 'effective learning', 'interesting and motivating class', 'more interaction', 'more cooperation and collaboration', 'more engagement', 'useful class time', 'learning team work', 'control on time to learn', 'acquiring practical knowledge and skills', 'reducing stress', 'self-reflection and self-evaluation', 'learning to take responsibility', 'boosting self-confidence', 'more attention in class', 'receiving effective feedback', 'becoming autonomous', and 'satisfying all learning styles'. However, five students also complained that the approach put a heavy burden on students. Six students argued that poor internet connection and lack of adequate technological tools can cause difficulty for the students who study in poor areas of the country. Therefore, Therefore, positive outcomes can be achieved via the online flipped pedagogy although careful planning is also required