Search Results (18,475)

As a representative wide-bandgap semiconductor material, gallium nitride (GaN) has attracted increasing attention because of its superior material properties (e.g., high electron mobility, high electron saturation velocity, and critical electric field). For power electronics applications, and to take full advantage of the superiorities of the GaN material, the normally off operation is required based on an AlGaN/GaN heterostructure. For a commercial approach, GaN HEMTs with a p-GaN gate have become a research hotspot. The characteristics of p-GaN gate HEMTs have a significant relationship with gate structure, especially the contact type on the p-GaN layer. In this review, the necessity of normally off operation and the advantages of adopting a p-GaN gate are elaborated, followed by the theory of achieving normally off operation by p-GaN and critical fabrication processes. The various gate structures are discussed, including metal gate, junction gate and hybrid gate structures on the p-GaN layer, to improve threshold voltage. Meanwhile, the methods required to optimize breakdown voltage and monolithically integrated technologies are also demonstrated. This review outlines the development and future trends of p-GaN gate HEMTs for power systems. Full article

Drawing on Governance Theory and institutional perspectives, this study analyses the relationship between e-government use and SDG16-related institutional outcomes across 27 European countries during 2010–2022. Using longitudinal panel data estimations with country and year fixed effects, complemented by an exploratory cluster analysis, the paper examines how technological, economic, and demographic factors influence trust in public institutions, voice and accountability, and control of corruption. The results reveal substantial heterogeneity across institutional dimensions. Economic variables, particularly income per capita and unemployment, emerge as the most robust predictors of institutional performance. By contrast, the effects of technological variables weaken considerably once structural country heterogeneity is controlled for. The findings suggest that digitalisation is more strongly associated with institutional trust than with improvements in democratic accountability or corruption control. Cluster analysis identifies heterogeneous trajectories of e-government adoption across European countries, indicating that digitalisation does not automatically generate governance improvements in all contexts. Overall, the study shows that the effectiveness of e-government depends heavily on broader institutional and socio-economic conditions and highlights the importance of distinguishing structural cross-country differences from within-country longitudinal dynamics. Full article

Wireless power transfer (WPT), characterized by its excellent insulation properties and ease of maintenance, has recently emerged as a promising solution to the power supply challenges faced by online monitoring equipment on high-voltage transmission towers in complex environments. Existing research primarily relies on regular, closely wound solenoids to power these monitoring devices; however, this approach often makes it difficult to optimize the magnetic field distribution to maximize mutual inductance, thereby limiting transmission efficiency and power and hindering lightweight design. To address these issues, this paper proposes an optimized design scheme for variable-pitch (non-uniform) domino WPT coils based on insulator string structures. First, a parameter calculation model utilizing segmented current analysis is constructed to accurately determine the inductance of non-uniform solenoids, with simulations confirming an error rate below 5%. Subsequently, by integrating domino multi-coil theory into an elitist non-dominated sorting genetic algorithm (NSGA-II), dual-objective optimization is performed. Targeting maximum transmission efficiency and output power under spatial and insulation constraints, a set of Pareto optimal solutions is derived. Ultimately, a 113.7 W insulator domino coil WPT system prototype is constructed to validate the design’s stability. The proposed system achieves a maximum efficiency of 85.73%, with a single-stage load delivering up to 97.48 W. Full article

Enterprise systems are widely adopted in organizations, yet user acceptance remains a major challenge due to the complex interplay of cognitive, social, motivational, and innovation-related factors. Existing technology acceptance models often provide fragmented explanations by focusing on limited determinants. This study proposes TAM 4, an exploratory framework integrating constructs from the Technology Acceptance Model (TAM), Unified Theory of Acceptance and Use of Technology (UTAUT), Hedonic-Motivation System Adoption Model (HMSAM), and Diffusion of Innovation (DOI). The study was conducted in the context of enterprise application usage and professional enterprise system training environments involving organizational users, trainees, and practitioners. Data were collected from 115 enterprise system users (trainees and practitioners). To consolidate overlapping indicators and strengthen construct definition, principal component analysis (PCA) was applied, yielding seven higher-order constructs that explain 81.642% of cumulative variance. The framework was validated using PLS-SEM with three scenario-based structural models (full mediation, partial mediation, and direct effects). The results show that Model 3 provides the best fit and predictive performance (SRMR = 0.048; NFI = 0.786), indicating that enterprise system adoption is better explained through a direct effect structure rather than a purely mediated TAM pathway. The novelty of this study lies in introducing TAM 4 as a PCA-driven multi-theory acceptance model and evaluating its explanatory robustness through multi-scenario model comparison, offering practical insights for improving enterprise system implementation strategies. Full article

The rapidly aging global population is placing immense pressure on healthcare systems, which are struggling to meet the needs of older adults. Information and communication technologies (ICTs) are considered a key driver in supporting the development of age-friendly healthcare models. This scoping review aims to map and structure the multifaceted applications of ICTs in age-friendly healthcare, focusing on their design, benefits, challenges, and implementation in different contexts. We followed the PRISMA-ScR guidelines and conducted a systematic search of five major databases (Web of Science, Scopus, PubMed, ScienceDirect, and IEEE Xplore), supplemented with backward citation chaining to improve the robustness of literature identification. The results show that ICTs can help older adults by improving their access to healthcare information, enhancing their care coordination, supporting their independent living, and personalizing their health management. Key challenges include user experience issues for older adults, data privacy and security concerns, and implementation barriers related to resources and professional support. Effective implementation of ICTs requires greater emphasis on age-centered design, robust data governance, and scalable integration with existing healthcare systems. We further propose a Technology Design–Scenario Application–Effect Evaluation (TD-SA-EE) analytical framework for ICT application in age-friendly healthcare; the framework is grounded in sociotechnical systems theory to provide explanatory insights beyond descriptive classification. This research provides insights into optimizing age-friendly healthcare through ICTs and contributes to fully leveraging ICTs in building sustainable and equitable age-friendly healthcare systems. Full article

This study examined rural pre-service teachers’ preferences for online learning platforms, Telegram, WhatsApp, and Moodle discussion forums in the Open Distance e-Learning environment. This group of students experiences digital illiteracy, limited access to assistive technologies, and network challenges, which may prevent them from optimally utilising formal learning platforms such as Moodle. They can, however, use Telegram and WhatsApp, as they regularly engage informally on these platforms. Against this backdrop, this study explored rural pre-service teachers’ experiences with Moodle and these social media platforms in an Open-Distance e-Learning space. This study employed a descriptive, qualitative case study with semi-structured interviews, guided by Siemens’ Connectivism theory. Fifteen student teachers from the College of Education in an ODeL institution were purposively sampled to provide in-depth insights into their lived experiences of platform use. The findings revealed that, although each platform served a unique instructional function, their perceived professionalism, safety, and interactivity differed substantially. Social media platforms such as Telegram and WhatsApp were lauded for their immediacy, accessibility, and low bandwidth usage, chiefly among rural pre-service teachers from economically disadvantaged communities. However, participants perceived these platforms as unprofessional, disruptive, and unsafe. Conversely, Moodle’s discussion forum was viewed as a credible, structured space that fostered academic discipline through the presence and guidance of lecturers. These contrasting perceptions highlight tensions between accessibility and academic regulation within ODeL environments. Although prior studies support incorporating social media platforms into LMSs, this research extends this discourse by emphasising the need to balance accessibility, interaction, and academic integrity within resource-constrained contexts. The study concludes that social media platforms and discussion forums can complement each other in ODeL, encouraging student interaction and inclusion, while discussion forums ensure educational rigour, safety, and institutional integrity. Full article

Despite the growing participation of women in higher education worldwide, they continue to face persistent challenges in their career advancement, including limited promotion opportunities, underrepresentation in leadership positions, lower research productivity, and unequal access to institutional resources. These challenges are shaped by a range of structural, institutional, and socio-cultural constraints within academia. Understanding these influencing factors is essential for promoting gender equity within universities. This study investigates the factors influencing the career advancement-related challenges experienced by women academics in Jordanian higher education institutions, focusing on career experience, family responsibilities, and organisational support. Grounded in Gendered Organisations Theory, Work-Family Conflict Theory, and Social Support Theory, the study develops and empirically tests an integrated conceptual model. Data were collected through a questionnaire survey of women academics across Jordanian universities. The quantitative data were analysed using Partial Least Squares Structural Equation Modelling (PLS-SEM), while qualitative responses on strategies for overcoming challenges were examined using directed qualitative content analysis. The findings indicate that family responsibilities represent the most influential driver of perceived challenges, highlighting the continuing tension between professional and domestic roles. Career experience is found to reduce perceived challenges, suggesting that accumulated professional capital and institutional familiarity enhance women’s ability to navigate academic environments. Organisational and social support not only directly reduce perceived challenges but also buffer the impact of family responsibilities. Multi-group analysis further reveals differences in the strength of these relationships between teaching-research academics and those occupying leadership roles. The qualitative results identify key strategies for addressing these challenges, including mentoring systems, flexible institutional policies, professional networking, and leadership development initiatives. By integrating structural modelling with qualitative insights, this study advances understanding of the complex dynamics shaping women’s academic careers and provides evidence-based recommendations for fostering more inclusive and supportive higher education environments. Full article

Developing efficient and sustainable catalysts for advanced oxidation processes (AOPs) to remove endocrine-disrupting compounds remains a critical challenge. In this study, a defect-engineered MnFe₂O₄@SBC composite was synthesized by loading spinel MnFe₂O₄ onto sewage sludge-derived biochar (SBC) prepared at different calcination temperatures, and applied for efficient periodate (PI) activation toward bisphenol A (BPA) degradation. The catalytic performance exhibited a volcano-type dependence on calcination temperature, with MnFe₂O₄@SBC-750 achieving the highest BPA removal efficiency (98.6% within 30 min). Structural characterization revealed that MnFe₂O₄@SBC-750 possessed an optimized carbon structure with a balance between defect sites and graphitized domains. Mechanistic investigations demonstrated that multiple reactive oxygen species, including ^•OH, O₂^•−, IO₃^• and ¹O₂, were involved in BPA degradation. LC-MS analysis identified key transformation intermediates and proposed degradation pathways, while toxicity assessment confirmed reduced ecological risks after treatment. Density functional theory (DFT) calculations indicated that MnFe₂O₄@SBC significantly enhanced PI adsorption and activation by promoting interfacial electron transfer and elongating the I-O bond in IO₄⁻. Notably, MnFe₂O₄@SBC-750 exhibited the strongest electron transfer capability, attributed to the optimal regulation of defect density and graphitization degree, which facilitated π-d electronic coupling at the MnFe₂O₄-SBC interface. Overall, this work elucidates the critical role of defect regulation in spinel biochar-based catalysts for oxidant activation and provides a sustainable strategy for converting sewage sludge into high-performance catalysts for water purification. Full article

Previous studies have shown that, after postoperative recovery from upper and lower gastrointestinal surgery for cancer, patients use peculiar modalities to describe their health. The purpose of this study is to determine how upper and lower gastrointestinal cancer surgery is considered by patients when they set their health. A structured interview was developed and 47 consecutive patients were interviewed postoperatively. Answers were analyzed through M.A.D.I.T., a quantitative and qualitative methodology that allows for the detection of discursive processes comprising the text, beyond thematic analysis. Four dimensions have been analyzed: representation of the postoperative period in daily life; use of resources; participation in achieving the clinical objective after hospital discharge; and continuing to respect the surgeons’ indications. A corpus of 2374 text occurrences was analyzed. Without differences between types of surgery, surgical patients described the time after surgical intervention as a critical scenario. Patients expressed their personal opinions, expecting normality after surgery and having difficulty envisioning the future: their representation of inflexibility in the postoperative period prevented them from finding new coping strategies. Overall, across all four dimensions, participants used stabilization discursive modalities in more than 50% of cases, representative of a situation bound within strict ties and personal theories. When defining their health, cancer surgery patients tend not to consider their condition as a new and different one from before; they imagine that they will be able to fully resume their previous habits. However, this can risk undermining the achievement of the clinical objective. Thus, during early surgical consultations, as well as in surgical recovery, exploring differences after surgery and solutions could help patients in their engagement with surgical outcomes and consequences. Full article

Against the backdrop of the rapid development of generative artificial intelligence (GenAI), exploring preschool teachers’ willingness to adopt technology is critical for advancing their educational applications. However, this area remains underexplored. To address this gap, this study draws on the Unified Theory of Acceptance and Use of Technology (UTAUT) to develop a research model incorporating performance expectancy, effort expectancy, social influence, facilitating conditions, perceived risks, and tech-savviness. Using a sequential mixed-methods design, we recruited 434 teachers to participate in a GenAI teaching-application workshop, collected 399 valid questionnaires for structural equation modeling, and conducted 15 in-depth interviews. Quantitative results indicate that performance expectancy, social influence, and tech-savviness are positively associated with preschool teachers’ intention to use GenAI, while perceived risk is negatively associated; effort expectancy and facilitating conditions show no significant association. Due to methodological limitations including high inter-construct correlations and potential common method bias, these findings should be viewed as exploratory rather than conclusive. Qualitative interviews support these relationships and provide further explanatory insights. The mixed-methods results offer preliminary hypotheses regarding GenAI adoption among preschool teachers, and future confirmatory research is needed to verify their generalizability, especially in collectivist cultural contexts. Full article

This paper advances a comprehensive controllability framework for Prabhakar fractional differential systems ($\mathcal{PFDS}$s) of order $\eta \in (1,2)$ with nonlocal initial conditions, where the second-order setting requires the joint specification of both an initial state and an initial velocity. Explicit solution representations for four structurally distinct classes of second-order Prabhakar systems are derived via the Laplace transform method and Neumann series expansions, revealing that the placement of the forcing term directly in the system or under the Prabhakar fractional integral operator produces fundamentally different convolution kernels. For linear integro-differential systems, necessary and sufficient controllability conditions are established through a Gramian rank criterion with an explicit norm-bounded control law, while for nonlinear systems, sufficient conditions are obtained via the Schauder fixed-point theorem under an asymptotic growth condition. Three numerical examples validate the theory: a three-dimensional linear system and a two-dimensional nonlinear integro-differential system achieve terminal errors of order ${10}^{-12}$ and ${10}^{-7}$, respectively, and a Prabhakar fractional mass–spring–damper system with viscoelastic hereditary damping demonstrates direct physical relevance, with all theoretical conditions verified and a terminal error of $7.42\times {10}^{-5}$ confirming precise rest-position steering by the Gramian-based control law. Full article

The high-value utilization of construction and demolition waste is critical for sustainable development in the building sector. However, in construction and demolition waste (CDW) recycling supply chains, existing studies lack a systematic analysis of pricing mechanisms for such recycled CDW as substrate products, particularly regarding interest coordination and the quantification of green value. To reveal the bargaining mechanism between farmers as recyclers and processors and supermarkets as retailers under an asymmetric bargaining structure, this study applies Nash bargaining theory to construct a dynamic game model. The study revealed that (1) when the green degree of a product reaches a certain level, it can obtain a sustainable market premium and create a stable income space for both parties. (2) The relative strength of the bargaining power between the two sides significantly affects the impact of market base scale changes on profit distribution. When the bargaining power of the supermarket is lower than the threshold and the bargaining power of the farmers is higher than the threshold, the difference in profit between the farmers and the supermarket is negatively correlated with the market base scale of the CDW as a substrate. (3) The green sensitivity level of consumers affects the difference in profit of the main body with the government subsidy to farmers. This level is determined by the value of the green sensitivity coefficient of consumers and presents a differentiated adjustment effect in different value ranges, which in turn affects the transmission direction of government subsidies to profit distribution. (4) When the green sensitivity coefficient and the green communication intensity of farmers and the investment level are lower than the corresponding critical values, the difference in social welfare with or without subsidies is positively correlated with the amount of the subsidy. This study provides decision support for farmers and supermarkets in designing rational bargaining strategies and offers insights for improving coordination and sustainability in construction and demolition waste recycling supply chains. Full article

Thin rectangular plates, due to their small thickness relative to length and width and their high strength-to-weight ratio, are widely used in structural elements such as ship hulls, bridge decks, and aircraft wings. They are prone to nonlinear buckling under compressive forces, especially under biaxial in-plane compressive loading with large displacements, where linear theories often fail and membrane stresses complicate analysis. This study aimed to formulate a general mathematical equation for buckling analysis of thin rectangular isotropic plates with large displacements subject to biaxial in-plane forces using the Ritz potential energy functional method, and incorporates both geometric and material nonlinearities. Based on the formulated general equation, a specific equation for an all-round simply supported (SSSS) plate was developed using polynomial displacement shape function to determine the stiffness characteristics. Numerical values for critical buckling and post-buckling loads under biaxial compression for a square plate case were obtained. To validate these results, a comparison with values in the literature was made and the results show high consistency. The uniaxial buckling deviations ranged 0.047–0.10%, while undeformed biaxial buckling coefficients across varying aspect ratios and loading ratios (n = Ny/Nx) showed near-zero differences. From the two studies used for comparison, the maximum deviation is 24.42% and the minimum deviation is 1.12%. This indicates that the new model is adequate. Also, the adequacy of this new equation can be judged based on the simplicity of the formulation, and the closed agreement of the obtained numerical results with established results in the literature. This research enhances theoretical understanding of nonlinear buckling in thin plates and offers practical insights for improving structural reliability and efficiency in civil, mechanical, aerospace, and marine engineering. Therefore, the conclusion is that the model is suitable for buckling and post-buckling analysis of thin rectangular isotropic plates. Full article

Teacher coaching is a widely used approach to support teacher professional development, yet the relational and psychological factors that influence coaching outcomes remain underexplored. Guided by the Expectancy-Value Theory and prior literature, this study examined the role of coaching relationships, teacher self-efficacy, and teachers’ motivation for coaching in the coaching process, with two key outcomes: teachers’ acceptability of coaching and perceived stress. A sample of 308 K-12 teachers from the United States completed relevant measures. Structural equation modeling revealed that high-quality coaching relationships were significantly associated with greater acceptability, self-efficacy, and motivation, particularly increased perceived benefits and reduced reservations. Coaching relationships and coaching acceptability were indirectly associated via self-efficacy and perceived benefits. The indirect association between coaching relationships and stress was fully explained through self-efficacy. These findings underscore the importance of fostering strong relationships with teachers and addressing motivational components to enhance the effectiveness of coaching interventions. Full article

A systematic first-principles density functional theory (DFT) study was performed using the Perdew–Burke–Ernzerhof (PBE) generalized gradient approximation (GGA) functional combined with ultrasoft pseudopotentials (USPPs), as implemented in the CASTEP code. The PBE-GGA functional was chosen because it provides a well-balanced description of both metallic and covalent bonding characteristics at the Fe/Ti₃SiC₂ interface. To elucidate the interfacial bonding mechanisms and heterogeneous nucleation behavior of Ti₃SiC₂ particles in iron-based composites. The structural stability, work of adhesion, interfacial energy, and electronic properties of the Fe(111)/Ti₃SiC₂(0001) interface were comprehensively investigated. A total of eighteen interface models were constructed, encompassing six distinct Ti₃SiC₂(0001) terminations: C(TiC), C(TiSi), TiC(TiC), TiC(TiSi), TiSi, and Si, and three stacking sequences (OT, MT, and HCP). The results demonstrate that the C(TiC)-terminated interface with HCP stacking exhibits the highest work of adhesion (9.25 J·m⁻²) and the lowest interfacial energy, thus representing the most thermodynamically stable configuration. Analysis of the partial density of states (PDOS) and charge density difference reveals that this exceptional stability originates from strong covalent bonding between Fe 3d and C 2p orbitals at the interface, accompanied by pronounced charge accumulation in the interfacial region. Furthermore, the work of adhesion of this interface substantially exceeds that of the fcc-Fe/fcc-Fe melt interface, confirming the high potency of Ti₃SiC₂ particles as heterogeneous nucleation substrates for Fe grains. These findings provide an atomistic framework for understanding the enhanced nucleation and robust interfacial cohesion observed in Fe/Ti₃SiC₂ composite coatings, and offer theoretical guidance for the design of advanced iron-based MAX phase composites. Full article