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{"title":"Human–Robot Co-Facilitation in Collaborative Learning: A Comparative Study of the Effects of Human and Robot Facilitation on Learning Experience and Learning Outcomes","authors":"Ilona Buchem, Stefano Sostak, Lewe Christiansen","doi":"10.3390/j7030014","DOIUrl":"https://doi.org/10.3390/j7030014","url":null,"abstract":"Collaborative learning has been widely studied in higher education and beyond, suggesting that collaboration in small groups can be effective for promoting deeper learning, enhancing engagement and motivation, and improving a range of cognitive and social outcomes. The study presented in this paper compared different forms of human and robot facilitation in the game of planning poker, designed as a collaborative activity in the undergraduate course on agile project management. Planning poker is a consensus-based game for relative estimation in teams. Team members collaboratively estimate effort for a set of project tasks. In our study, student teams played the game of planning poker to estimate the effort required for project tasks by comparing task effort relative to one another. In this within- and between-subjects study, forty-nine students in eight teams participated in two out of four conditions. The four conditions differed in respect to the form of human and/or robot facilitation. Teams 1–4 participated in conditions C1 human online and C3 unsupervised robot, while teams 5–8 participated in conditions C2 human face to face and C4 supervised robot co-facilitation. While planning poker was facilitated by a human teacher in conditions C1 and C2, the NAO robot facilitated the game-play in conditions C3 and C4. In C4, the robot facilitation was supervised by a human teacher. The study compared these four forms of facilitation and explored the effects of the type of facilitation on the facilitator’s competence (FC), learning experience (LX), and learning outcomes (LO). The results based on the data from an online survey indicated a number of significant differences across conditions. While the facilitator’s competence and learning outcomes were rated higher in human (C1, C2) compared to robot (C3, C4) conditions, participants in the supervised robot condition (C4) experienced higher levels of focus, motivation, and relevance and a greater sense of control and sense of success, and rated their cognitive learning outcomes and the willingness to apply what was learned higher than in other conditions. These results indicate that human supervision during robot-led facilitation in collaborative learning (e.g., providing hints and situational information on demand) can be beneficial for learning experience and outcomes as it allows synergies to be created between human expertise and flexibility and the consistency of the robotic assistance.","PeriodicalId":73524,"journal":{"name":"J","volume":"54 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141649918","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synergisms between Surfactants, Polymers, and Alcohols to Improve the Foamability of Mixed Systems","authors":"L. Alves, Solange Magalhães, Cátia Esteves, Marco Sebastião, Filipe Antunes","doi":"10.3390/j7020010","DOIUrl":"https://doi.org/10.3390/j7020010","url":null,"abstract":"In order to produce detergents with improved performance and good market acceptability, it is crucial to develop formulations with improved foamability and cleaning performance. The use of a delicate balance of surfactants and additives is an appealing strategy to obtain good results and enables a reduction in the amount of chemicals used in formulations. Mixtures of hydrophobically modified linear polymers and surfactants, as well as balanced mixtures with co-surfactants and/or hydrotropes, are the most effective parameters to control foamability and foam stability. In the present study, the effect of the addition of hydrophobically modified linear polymers, nonionic co-surfactants and hydrotropes, and their mixtures to anionic and zwitterionic surfactant aqueous solutions was evaluated. It was found that the presence of the hydrophobically modified polymer (HM-P) prevented the bubbles from bursting, resulting in better stability of the foam formed using zwitterionic surfactant solutions. Also, the surfactant packing was inferred to be relevant to obtaining foamability. Mixtures of surfactants, in the presence of a co-surfactant or hydrotrope led, tendentially, to an increase in the critical packing parameter (CPP), resulting in higher foam volumes and lower surface tension for most of the studied systems. Additionally, it was observed that the good cleaning efficiency of the developed surfactant formulations obtained a higher level of fat solubilization compared to a widely used brand of commercial dishwashing detergent.","PeriodicalId":73524,"journal":{"name":"J","volume":" 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140991507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aerodynamic Modification of High-Rise Buildings by the Adjoint Method","authors":"Amirfarhang Nikkhoo, A. Esmaeili, Shayan Rabizade, Majid Zamiri","doi":"10.3390/j7010004","DOIUrl":"https://doi.org/10.3390/j7010004","url":null,"abstract":"This study presents a novel numerical methodology that is designed for the dynamic adjustment of three-dimensional high-rise building configurations in response to aerodynamic forces. The approach combines two core components: a numerical simulation of fluid flow and the adjoint method. Through a comprehensive sensitivity analysis, the influence of individual variables on aerodynamic loads, including lift and drag coefficients, is assessed. The findings underscore that the architectural design, specifically the building’s construction pattern, exerts the most substantial impact on these forces, accounting for a substantial proportion (76%). Consequently, the study extends its evaluation to the sensitivity of fluid flow across various sections of the tower by solving the adjoint equation throughout the entire fluid domain. As a result, the derived sensitivity vector indicates a remarkable reduction of approximately 31% in the applied loads on the tower. This notable improvement has significant implications for the construction of tall buildings, as it effectively mitigates aerodynamic forces, ultimately enhancing the overall comfort and structural stability of these architectural marvels.","PeriodicalId":73524,"journal":{"name":"J","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139865984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aerodynamic Modification of High-Rise Buildings by the Adjoint Method","authors":"Amirfarhang Nikkhoo, A. Esmaeili, Shayan Rabizade, Majid Zamiri","doi":"10.3390/j7010004","DOIUrl":"https://doi.org/10.3390/j7010004","url":null,"abstract":"This study presents a novel numerical methodology that is designed for the dynamic adjustment of three-dimensional high-rise building configurations in response to aerodynamic forces. The approach combines two core components: a numerical simulation of fluid flow and the adjoint method. Through a comprehensive sensitivity analysis, the influence of individual variables on aerodynamic loads, including lift and drag coefficients, is assessed. The findings underscore that the architectural design, specifically the building’s construction pattern, exerts the most substantial impact on these forces, accounting for a substantial proportion (76%). Consequently, the study extends its evaluation to the sensitivity of fluid flow across various sections of the tower by solving the adjoint equation throughout the entire fluid domain. As a result, the derived sensitivity vector indicates a remarkable reduction of approximately 31% in the applied loads on the tower. This notable improvement has significant implications for the construction of tall buildings, as it effectively mitigates aerodynamic forces, ultimately enhancing the overall comfort and structural stability of these architectural marvels.","PeriodicalId":73524,"journal":{"name":"J","volume":"36 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139805960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Blockchain in Smart Grids: A Bibliometric Analysis and Scientific Mapping Study","authors":"Georgios Lampropoulos","doi":"10.3390/j7010002","DOIUrl":"https://doi.org/10.3390/j7010002","url":null,"abstract":"To achieve sustainability and fulfill sustainable development goals, the digitalization of the power sector is vital. This study aims to examine how blockchain can be integrated into and enrich smart grids. In total, 10 research questions are explored. Scopus and Web of Science (WoS) were used to identify documents related to the topic. The study involves the analysis of 1041 scientific documents over the period 2015–2022. The related studies are analyzed from different dimensions including descriptive statistics, identification of the most common keywords and most widely used outlets, examination of the annual scientific production, the analysis of the most impactful and productive authors, countries, and affiliations. The advancement of the research focus and the most popular topics are also examined. Additionally, the results are analyzed, the main findings are discussed, open issues and challenges are presented, and suggestions for new research directions are provided. Based on the results, it was evident that blockchain plays a vital role in securing smart grids and realizing power sector digitalization, as well as in achieving sustainability and successfully meeting sustainable development goals.","PeriodicalId":73524,"journal":{"name":"J","volume":"64 14","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139449248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Overview of Mathematical Methods Applied in the Biomechanics of Foot and Ankle–Foot Orthosis Models","authors":"H. Nazha, S. Szávai, D. Juhre","doi":"10.3390/j7010001","DOIUrl":"https://doi.org/10.3390/j7010001","url":null,"abstract":"Ankle–foot orthoses (AFOs) constitute medical instruments designed for patients exhibiting pathological gait patterns, notably stemming from conditions such as stroke, with the primary objective of providing support and facilitating rehabilitation. The present research endeavors to conduct a comprehensive review of extant scholarly literature focusing on mathematical techniques employed for the examination of AFO models. The overarching aim is to gain deeper insights into the biomechanical intricacies underlying these ankle–foot orthosis models from a mathematical perspective, while concurrently aiming to advance novel models within the domain. Utilizing a specified set of keywords and their configurations, a systematic search was conducted across notable academic databases, including ISI Web of Knowledge, Google Scholar, Scopus, and PubMed. Subsequently, a total of 23 articles were meticulously selected for in-depth review. These scholarly contributions collectively shed light on the utilization of nonlinear optimization techniques within the context of ankle–foot orthoses (AFOs), specifically within the framework of fully Cartesian coordinates, encompassing both kinematic and dynamic dimensions. Furthermore, an exploration of a two-degree-of-freedom AFO design tailored for robotic rehabilitation, which takes into account the interplay between foot and orthosis models, is delineated. Notably, the review article underscores the incorporation of shape memory alloy (SMA) elements in AFOs and overviews the constitutive elastic, viscoelastic, and hyperelastic models. This comprehensive synthesis of research findings stands to provide valuable insights for orthotists and engineers, enabling them to gain a mathematical understanding of the biomechanical principles underpinning AFO models and fostering the development of innovative AFO designs.","PeriodicalId":73524,"journal":{"name":"J","volume":"71 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139164318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Comparative Study of Finite Element Method and Hybrid Finite Element Method–Spectral Element Method Approaches Applied to Medium-Frequency Transformers with Foil Windings","authors":"S. Pourkeivannour, Joost S. B. van Zwieten, L. Friedrich, M. Curti, E. Lomonova","doi":"10.3390/j6040041","DOIUrl":"https://doi.org/10.3390/j6040041","url":null,"abstract":"This study aims to improve the computational efficiency of the frequency domain analysis of medium-frequency transformers (MFTs) with the presence of large clearance distances and fine foil windings. The winding loss and magnetic energy in MFTs in the medium-frequency range are calculated utilizing a finite element method (FEM) using common triangular and alternative rectilinear mesh elements. Additionally, in order to improve the computational efficiency of the calculations, a spectral element method (SEM) is coupled with a FEM, thus creating a hybrid FEM–SEM formulation. In such a hybrid approach, the FEM is used to calculate the current density distribution in the two-dimensional (2D) cross-section of the foil conductors to achieve reliable accuracy, and the SEM is adopted in the nonconducting clearance distances of the winding window to reduce the system of equations. The comparative analysis of the calculated resistance and reactance of the under-study models showed that the FEM with rectilinear mesh elements and the FEM–SEM model outperformed the FEM with triangular mesh elements in terms of accuracy and computational cost. The hybrid FEM–SEM model enables a reduced system of equations for modeling the electromagnetic behavior of MFTs. This research provides valuable insights into both the computational approaches and meshing challenges in the analysis of MFTs and offers a foundation for future research on the design and optimization of MFTs.","PeriodicalId":73524,"journal":{"name":"J","volume":"19 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139004079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relationship between Plasma Lipopolysaccharide Concentration and Health Status in Healthy Subjects and Patients with Abnormal Glucose Metabolism in Japan: A Preliminary Cross-Sectional Study","authors":"Nobuo Fuke, Shojiro Sawada, T. Ito-Sasaki, Kumi Y. Inoue, Yusuke Ushida, Ikuo Sato, T. Matsue, Hideki Katagiri, Hiroyuki Ueda, Hiroyuki Suganuma","doi":"10.3390/j6040040","DOIUrl":"https://doi.org/10.3390/j6040040","url":null,"abstract":"Lipopolysaccharides are components of Gram-negative bacteria. The relationship between blood lipopolysaccharide levels and health status has mainly been investigated in Europe, and there is a lack of information about Asia, particularly Japan. This study aimed to investigate the relationship between blood lipopolysaccharide levels and health status in the Japanese. We conducted two cross-sectional studies in 36 healthy subjects (Study 1) and 36 patients with abnormal glucose metabolism (AGM; Study 2). The plasma lipopolysaccharide concentration in healthy subjects was positively correlated with body mass index. The plasma lipopolysaccharide concentration in AGM patients was obviously higher than that in healthy subjects. Furthermore, in AGM patients, the plasma lipopolysaccharide concentration was positively correlated with C-peptide, fasting plasma glucose levels, triglycerides, and stage of diabetic nephropathy. The plasma lipopolysaccharide concentration was also negatively correlated with 20/(C-peptide × fasting plasma glucose), an indicator of insulin resistance, and high-density lipoprotein cholesterol. In particular, the correlation between plasma lipopolysaccharide concentration and triglycerides in AGM patients was maintained in multiple regression analyses adjusted for age, sex, or body mass index. These results suggest a possible role of lipopolysaccharides in obesity in healthy subjects and in the deterioration of triglyceride metabolism in AGM patients in the Japanese population.","PeriodicalId":73524,"journal":{"name":"J","volume":"62 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139198887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antioxidant Activity of Selected Medicinal Plants Used by Traditional Herbal Practitioners to Treat Cancer in Malawi","authors":"F. F. Masumbu, J. Kamanula, A. Mwakikunga, Bonface Mwamatope, D. Tembo","doi":"10.3390/j6040039","DOIUrl":"https://doi.org/10.3390/j6040039","url":null,"abstract":"This study evaluated the phytochemical composition and antioxidant activity of Piliostigma thonningii (Schumach.) Milne-Redh, Psorospermum febrifugum Spach, Inula glomerata Oliv. and Hiern, Zanthoxylum chalybeum Engl. and Monotes africanus A.DC., claimed to treat cancer by Malawian traditional herbal practitioners. Ground and dried plant extracts were analyzed for total phenolic content (TPC), total flavonoid content (TFC), total alkaloid content (TAC), ferric reducing antioxidant power (FRAP) and 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) using standard assays. The TPC, TFC, and TAC ranged from 539 ± 2.70 to 4602 ± 32 mg GAE/g DW, 6.18 ± 0.03 to 64.04 ± 0.16 mg QE/g DW and 19.25 ± 0.07 to 76.05 ± 0.36 mg CE/g DW, respectively, and the variations were significant, p < 0.05. FRAP values ranged from 82.15 ± 0.7 to 687.28 ± 0.71 mg TEAC/g DW and decreased in the following order: P. thoningii (Schumach.) Milne-Redh > P. febrifugum Spach > M. africanus A.DC > Z. chalybeum Engl > I. glomerata Oliv. and Hiern. The scavenging activity (SA50) of the extracts ranged from 0.09 ± 0.01 to 1.57 ± 0.01 μg/mL of extract with P. thonningii (Schumach.) Milne-Redh showing the lowest value. Based on the levels of phenolic compounds and their antioxidant activity, the plants in this study could be considered for use as medicinal agents and sources of natural bioactive compounds and antioxidants.","PeriodicalId":73524,"journal":{"name":"J","volume":"287 3-4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139257593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Photocatalytic Reduction of Cr(VI) and Pb(II) with Biogenically Synthesized Copper Oxide Nanoparticles Using an Extract of the Myriophyllum spicatum Plant","authors":"Opeyemi A. Oyewo, Seshibe S. Makgato","doi":"10.3390/j6040037","DOIUrl":"https://doi.org/10.3390/j6040037","url":null,"abstract":"The biogenic synthesis of copper oxide nanoparticles was explored using the Myriophyllum spicatum plant through a process involving co-precipitation and was utilized as an effective photocatalyst for the reduction of Cr(VI) and Pb(II) ions in an aqueous solution. The plant-mediated CuO nanoparticles were characterized using microscopic techniques (TEM and SEM), FT-IR, and XRD analyses. The amount of the reduced metal ions was determined by UV–visible and Atomic Absorption (AA) spectrophotometers. The analyses of the functional group present in the leaf extract revealed the type of bioactive molecules that were involved in the formation of copper oxide nanoparticles. The nanoparticles were used in the photo-enhanced reduction of hexavalent Cr and divalent Pb ions, and the impact of solution pH, initial metal concentrations, and photocatalyst dosage was investigated to establish the optimal performance of the CuO nanoparticles. Results revealed a direct association between the reduction of metal ions and catalyst dosage in both cases. A maximum percentage reduction of 89.2% and 79.1% was achieved for Cr(VI) and Pb(II), respectively, using 3 g of the CuO nanoparticles. This confirms that the CuO nanoparticles exhibited higher efficiency for Cr(VI) reduction as compared to Pb(II) reduction and indicates that CuO nanoparticles are a promising photocatalyst that is capable of reducing these metal ions into less toxic products.","PeriodicalId":73524,"journal":{"name":"J","volume":"31 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135871862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}