Search Results (6,950)

Based on extensive ethnographic fieldwork conducted in Mianning County, Liangshan Yi Autonomous Prefecture between 2023 and 2024, this paper analyzes the “xiō bū” (ꑭꁮ) ritual of the Liangshan Yi people. Framed within contemporary approaches to religious anthropology and social memory theory, the study explores how this ritual constructs Yi ecological ethics, social integration, and cultural identity through nature worship, ancestral spirit beliefs, and ritual practices. The ethnographic evidence reveals that the “xiō bū” ritual, by designating wooded mountains as sacred space and performing sacrifices to nature deities and ancestral spirits, integrates “humans—nature—ancestors” into a symbiotic system of the “community of life.” This reflects the Yi people’s relational ontology and embedded ecological knowledge. The sacrificial offerings, shared meals, and purification practices in the ritual not only reinforce reverence for nature through symbolic acts but also unify the community through Durkheimian “collective effervescence,” thereby restoring the community’s spiritual order. As a carrier of social memory, the “xiō bū” ritual, through epic chanting, symbolic performances (such as clothing, ritual implements), and bodily practices (like the ritual specialist’s movements), embeds individual memories into the collective historical narrative of the group, dynamically constructing the cultural boundaries of the “Yi” people. The ritual specialists (Bimo or Suni), as intermediaries of knowledge and power, maintain religious authority through bricolage-like symbolic reorganization and foster the creative transformation of tradition in response to the challenges of modernity. The study further reveals that while the ritual faces challenges in the contemporary context, such as secularization and population mobility, it continues to activate ethnic identity by simplifying rituals, preserving core symbols, and coupling with ecological discourses, offering a model for the modern adaptation of traditional religions. This paper argues that ritual studies should engage with contemporary theoretical approaches like the ontological turn, focus on the agency of individuals, and reflect on the insights traditional knowledge systems offer in the face of globalization and ecological crises. Full article

The aerodynamic performance of unmanned aerial vehicles (UAVs) with non-conventional geometries is a growing area of interest, particularly for improving stability and maneuverability. This study investigates the influence of the dihedral angle on the aerodynamic behavior and overall performance of drones configured in an X-wing layout. Four configurations with dihedral angles of 0°, 15°, 30°, and 45° were analyzed to assess how varying the wing inclination affects flight characteristics. Computational fluid dynamics (CFD) simulations were conducted to evaluate the aerodynamic forces and moments acting on each configuration under controlled conditions. Following the aerodynamic analysis, a performance assessment was carried out to determine the implications of each dihedral angle on parameters such as range, endurance, rate of climb, angle of climb or turn rate. The results indicate that increasing the dihedral angle can enhance maneuverability but may lead to trade-offs in aerodynamic efficiency, particularly at higher angles. The 15° and 30° configurations demonstrated a favorable balance between maneuverability and performance. These findings provide insight into the design optimization of X-wing UAVs and highlight the potential of dihedral angle tuning as a means to tailor drone behavior for specific operational needs. Full article

The informal street food sector serves as a vital component of urban economies in South Africa, providing affordable nutrition and employment. However, this industry struggles to comply with required health and safety practices and standards. This study protocol outlines a mixed-methods investigation into hygiene practices, regulatory compliance, and the intersection with business sustainability among informal food vendors in Johannesburg’s inner city. This study aims to investigate how vendors’ perceptions of health risks and benefits influence compliance behaviours and, in turn, how these behaviours impact operational efficiency, financial stability, and customer trust. Grounded in the Health Belief Model (HBM) and the Balanced Scorecard (BSC) framework, the research seeks to explore both behavioural drivers and performance outcomes associated with hygiene adherence. The study will employ structured stall observations, semi-structured vendor interviews, and customer surveys across high-density vending zones. Quantitative data will be analysed using descriptive and inferential statistics, while qualitative data will be thematically analysed and triangulated with observed practices. The expected outcome is to identify key barriers and enablers of hygiene compliance and demonstrate how improved food safety practices contribute to business resilience, customer trust, and urban public health. The findings aim to inform inclusive policy and innovative business support strategies that integrate informal vendors into safer and more sustainable food systems. Full article

Background: Soft tissue stability around dental implant abutments is critical for maintaining a functional peri-implant seal. Yellow anodization is used to improve the aesthetic and surface characteristics of titanium abutments, yet its epithelial effects under more physiologically relevant 3D conditions remain insufficiently explored. Objective: To develop a 3D bioprinted in vitro peri-implant mucosa model and to compare epithelial cell responses on yellow anodized versus turned titanium abutment surfaces. Methods: Commercial Grade 5 (Ti6Al4V) titanium abutments were anodized and compared with turned controls. A collagen-based 3D bioprinted “collar-like” construct incorporating YD-38 epithelial cells was fabricated using a custom holder system to simulate peri-implant mucosal contact. Samples were cultured for 14 and 21 days. Cell distribution and morphology were assessed by optical microscopy and HE staining, while cytoskeletal organization was evaluated by TRITC-phalloidin/Hoechst staining and confocal microscopy. Quantitative fluorescence analysis was performed at 21 days. Results: Both surfaces supported epithelial coverage in the 3D environment. Anodized specimens showed more pronounced actin cytoskeletal organization and the presence of actin-rich, filamentous cellular extensions compared with turned controls. Quantitative image analysis demonstrated significantly higher TRITC-phalloidin signal intensity at 21 days on anodized samples (p < 0.001). Conclusions: Within the limitations of a 3D epithelial in vitro model using YD-38 cells, yellow anodization was associated with enhanced epithelial cytoskeletal organization compared with turned titanium. The presented 3D bioprinted platform may serve as a practical in vitro tool for screening abutment surface modifications relevant to peri-implant soft tissue integration. Full article

This study aims to explore the relationship between the digital financial literacy of homestay business owners and economic sustainability. A conceptual model is developed by integrating three primary constructs—performance expectancy, effort expectancy, and facilitating conditions—from the unified theory of acceptance and use of technology (UTAUT) with digital financial literacy and FinTech use by homestay business owners. Further, the effect of FinTech use on economic sustainability is examined through the interaction between facilitating conditions and financial inclusion. Data were collected from Southern India, and hypothesized relationships were tested after checking the measurement properties of the survey instrument. The findings indicate that (i) the digital financial literacy of homestay business owners is a precursor to FinTech use, which, in turn, is positively associated with economic sustainability; (ii) digital financial literacy interacting with performance expectancy (first moderator) and effort expectancy (second moderator) significantly influenced FinTech use; and (iii) FinTech use interacting with facilitating conditions (first moderator) and financial inclusion (second moderator) increased economic sustainability. The three-way interactions in this study provide insights into the boundary conditions that increase FinTech use and economic sustainability, particularly in the context of homestay businesses. The proposed digital financial literacy and FinTech adoption model contributes to the information technology adoption research by extending the UTAUT, in which performance expectancy and effort expectancy play a vital role in FinTech adoption by homestay business owners. The three-way model developed and tested, to the best of our knowledge, is the first of its kind in the Indian context and hence makes a pivotal contribution to the advancement of the UTAUT model through its application to homestay business owners. The implications for theory and practice are discussed. Full article

Computer-based engineering design tools can quicken the cadence for machine design, which enables companies to compete better in the global marketplace. The application of nonlinear optimization and tradespace analysis methods allows the exploration of design variables within dynamic mechanisms. In this paper, the design of a classical machine, the Seth Thomas pendulum street clock, which offered precision timekeeping and time display at the turn of the 20th century, will be investigated from a modern perspective. A mathematical model serves as the basis for the genetic algorithm optimization method to assess the system design in terms of accuracy, mass, quality factor, and bending stress. To validate the model, experimental data was collected on a 1906 Seth Thomas Model 04 movement. The engineering study findings indicate that the target accuracy, quality factor, and bending stress can be achieved with pendulum mass and gear thickness reductions of 1.4% and 50.3%, respectively. The tradespace exploration offers a visualization of the machine’s performance per design variable adjustments for greater insight into the original solution and subsequent recommended changes. Overall, this mechanical machine review enables an assessment of original design choices made over a century ago and provides an awareness of engineering’s progress during this period. Full article

Background/Objectives: Energy availability (EA), defined as the dietary energy remaining after exercise energy expenditure (EEE), is a central determinant of both health and performance in athletes. Chronic insufficient EA leads to low energy availability (LEA), which is an underlying mechanism of Relative Energy Deficiency in Sport (REDs). This narrative review critically explores the conceptual evolution of EA and LEA, summarizes current physiological evidence, and discusses methodological and practical challenges in their assessment and application in free-living athletes. Methods: Evidence from experimental and observational studies was reviewed to describe the hormonal, metabolic, and performance outcomes associated with LEA. Screening tools, including the Low Energy Availability in Females Questionnaire (LEAF-Q) and the Low Energy Availability in Males Questionnaire (LEAM-Q), were also evaluated for their validity and applicability in different sports contexts. Results: LEA is associated with alterations in thyroid and reproductive hormones, which, in turn, contribute to reduced resting metabolic rate, lower bone mineral density, and delayed recovery. While screening questionnaires can help identify athletes at risk, their accuracy varies by sport and individual characteristics. Incorporating hormonal and metabolic biomarkers provides a more direct and sensitive method for detecting physiological stress. Measuring dietary intake, EEE, endocrine balance and body composition in real-world settings remains a major methodological challenge. Combining hormonal, metabolic, and behavioral indicators may improve the identification of athletes experiencing LEA. Conclusions: EA plays a central role in the interaction between nutrition, exercise, and athlete health, but methodological limitations in its assessment may compromise accurate diagnosis. Improving measurement techniques and adopting integrated monitoring strategies are essential to improve early detection, guide individualized nutrition, and prevent RED-related health and performance impairments. Full article

This paper presents a microstructural, mineralogical, and mechanical study of low-carbon autoclaved concrete (AC), achieved by partially or fully replacing ordinary Portland cement (OPC) with ground-granulated blast furnace slag (BFS) and substituting lime with calcium carbide slag (CCS). Fourteen mixes were produced and evaluated in the green state and after autoclaving. Quantitative X-ray diffraction (XRD) using the Rietveld method, density, compressive strength, and life cycle assessment (LCA) were conducted. Results show that mixes containing BFS achieve green strengths equal to or higher than the OPC reference, ensuring integrity during autoclaving. Using BFS with an adequate calcium supply promotes the formation of pre-autoclave portlandite, which in turn favors tobermorite development and yields post-autoclave strengths comparable to the OPC reference. Partial lime replacement with CCS (50%) maintains mineralogy and strength, whereas excessive CCS may reduce available portlandite and lower strength. Life-cycle assessment indicates that raw material supply dominates emissions and that removing OPC cuts total CO₂ by 44% without compromising mechanical performance. These findings demonstrate the feasibility of OPC-lean/OPC-free, lime-optimized autoclaved concretes with substantially lower embodied impacts. Full article

This paper analyzes different approaches for the mathematical modeling and optimization of process parameters in the hard turning process of 42CrMo4 steel using a hybrid approach combining response surface methodology (RSM), multi-criteria decision making (MCDM), and machine learning through, support vector regression (SVR) with one-factor-at-a-time (OFAT) sensitivity analysis. Controlled process parameters such as cutting speed, depth of cut, feed, and insert radius are applied to conduct the experiments based on a full factorial experimental design. RSM was used to develop models that describe the effect of controlled parameters on surface roughness and cutting forces. Special emphasis was placed on the analysis of standardized residuals to evaluate the predictive capabilities of the RSM-developed model on an unseen data set. For all four outputs considered, analysis of the standardized residuals shows that over 97% of the points lie within ±3 standard deviations. A multi-criteria optimization technique was applied to establish an optimal combination of input parameters. The SVR model had high performance for all outputs, with coefficient of determination values between 89.91% and 99.39%, except for surface roughness on the test set, with a value of 9.92%. While the SVR model achieved high predictive accuracy for cutting forces, its limited generalization capability for surface roughness highlights the higher complexity and stochastic nature of surface formation mechanisms in the turning process. OFAT analysis showed that feed rate and depth of cut have been shown to be the most important input variables for all analyzed outputs. Full article

Mobile air cleaners have emerged as a practical solution for reducing indoor aerosol concentrations, particularly in the absence of HVAC systems. Their efficiency is typically assessed under standardised conditions, but how turbulence influences the effective air exchange rate indoors is not well understood. In this study, we present a systematic investigation of the impact of enhanced turbulence on aerosol decay in two room sizes (50 m³ and 200 m³) using a mobile air cleaner combined with different fan configurations. Particle counter measurements were conducted simultaneously with particle image velocimetry ($PIV$), enabling direct comparison of air exchange rates and flow field properties. Our results show that specific fan arrangements significantly modify turbulent kinetic energy ($TKE$) distributions and, in turn, alter the effective air exchange rate. In the smaller room, configurations generating higher $TKE$ brought the measured exchange rates closer to theoretical predictions, while in large rooms other arrangements led to noticeable deviations. We anticipate that these findings provide a reference framework for understanding the role of turbulence in indoor air cleaning performance, with implications for optimizing the operation and placement of mobile air cleaners in practical environments. Full article

Cooperative task allocation is one of the critical enablers for multi-Autonomous Underwater Vehicle (AUV) missions, but existing approaches often assume reliable communication that rarely holds in real underwater acoustic environments. We study here the performance and robustness of the Consensus-Based Bundle Algorithm (CBBA) for multi-AUV task allocation under realistically degraded underwater communication conditions with dynamically appearing tasks. An integrated simulation framework that incorporates a Dubins-based kinematic model with minimum turning radius constraints, a configurable underwater acoustic communication model (range, delay, packet loss, and bandwidth), and a full implementation of improved CBBA with new features, complemented by 3D trajectory and network-topology visualization. We define five communication regimes, from ideal fully connected networks to severe conditions with short range and high packet loss. Within these regimes, we assess CBBA based on task allocation quality (total bundle value and task completion rate), convergence behavior (iterations and convergence rate), and communication efficiency (message delivery rate, average delay, and network connectivity), with additional metrics on the number of conflicts during dynamic task reallocation. Our simulation results indicate that CBBA maintains performance close to the optimum when the conditions are good and moderate but degrades significantly when connectivity becomes intermittent. We then introduce a local-communication-based conflict resolution strategy in the face of frequent task conflicts under very poor conditions: neighborhood-limited information exchange, negotiation within task areas, and decentralized local decisions. The proposed conflict resolution strategy significantly reduces the occurrence of conflicts and improves task completion under stringent communication constraints. This provides practical design insights for deploying multi-AUV systems under weak underwater acoustic networks. Full article

Modern power transmission systems are required to meet increasingly stringent demands, including a wide range of transmission ratios, compact dimensions, high precision, energy efficiency, reliability, and thermal stability under dynamic operating conditions. Among the solutions that satisfy these requirements, cycloidal reducers are particularly prominent, with their application continuously expanding in industrial robotics, computer numerical control (CNC) machines, and military and transportation systems, as well as in the satellite industry. However, as with all mechanical power transmissions, friction in the contact zones of load-carrying elements in cycloidal reducers leads to power losses and an increase in operating temperature, which in turn results in a range of adverse effects. These undesirable phenomena strongly depend on lubrication conditions, namely on the type and properties of the applied lubricant. Although manufacturers’ catalogs provide general recommendations for lubricant selection, they do not address the fundamental tribological mechanisms in the most heavily loaded contact pairs. At the same time, the available scientific literature reveals a significant lack of systematic and experimentally validated studies examining the influence of lubricant type on the energetic and thermal performance of cycloidal reducers. To address this identified research gap, this study presents an analytical and experimental investigation of the effects of different lubricant types—primarily greases and mineral oils—on the thermal stability and efficiency of cycloidal reducers. The results demonstrate that grease lubrication provides lower total power losses and a more stable thermal operating regime compared to oil lubrication, while oil film thickness analyses indicate that the most unfavorable lubrication conditions occur in the contact between the eccentric bearing rollers and the outer raceway. These findings provide valuable guidelines for engineers involved in cycloidal reducer design and lubricant selection under specific operating conditions, as well as deeper insight into the lubricant behavior mechanisms within critical contact zones. Full article

Diagnosing faults in Permanent Magnet Synchronous Motors (PMSMs) is critical for ensuring their reliable operation, particularly in detecting internal short-circuit faults in the stator windings. These faults, such as inter-turn and inter-coil short circuits, can significantly affect motor performance and lead to costly downtime if not detected early. However, detecting these faults accurately, especially in the presence of operational noise and varying load conditions, remains a challenging task. To address this, a novel methodology is proposed for diagnosing and classifying fault severity in PMSMs using vibration and current data. The key innovation of the method is the combination of signal processing for both vibration and current data, to enhance fault detection by applying advanced feature extraction techniques such as root mean square (RMS), peak-to peak values, and spectral entropy in both time and frequency domains. Furthermore, a cooperative gain transformation is applied to amplify weak correlations between vibration and current signals, improving detection sensitivity, especially during early fault progression. In this study, the publicly available dataset on Mendeley, which consists of vibration and current measurements from three PMSMs with different power ratings of 1.0 kW, 1.5 kW, and 3.0 kW, was used. The dataset includes eight different levels of stator fault severity, ranging from 0% up to 37.66%, and covers normal operation, inter-coil short circuit, and inter-turn short circuit. The results demonstrate the effectiveness of the proposed methodology, achieving an accuracy of 96.6% in fault classification. The performance values for vibration and current measurements, along with the corresponding fault severities, validate the method’s ability to accurately detect faults across various operating conditions. Full article

The present study systematically investigates, for the first time, the combined influences of detonator position (top-edge and bottom-edge initiations) and anvil material (steel and sand) on the interfacial microstructure and mechanical performance of explosively welded A1050/AZ31 dissimilar joints. When welding was conducted using a steel anvil with the detonator positioned at the top edge, significant cracking occurred both at the surface and along the weld interface. In contrast, placing the detonator at the bottom edge noticeably reduced these defects. Moreover, the use of a sand anvil nullified these defects by damping the reflecting shockwaves and minimizing vibrations. Hardness measurements revealed substantial increase at the interface under all the conditions, with the highest value observed with the steel anvil. Welds subjected to top-edge detonation showed higher hardness values compared to those of welds subjected to bottom-edge detonation. Overall, the results suggest that sand anvils with bottom-edge detonation provide the optimal weld quality. The rigid steel anvil reflects the shockwave, generating high pressure and velocity at the interface, whereas the sand anvil absorbs a part of the shock energy, suppressing high-magnitude reflections. The position of the detonator influences the propagation dynamics of the detonation wave and the resulting collision velocity, which in turn, affect the interfacial morphology and overall quality of the weld. Full article

This study examines the dynamics of economic freedom in nine advanced democracies in comparison to China over the 1970–2022 period. Using data from the Fraser Institute and the Manifesto Project Database, we apply a Bayesian time-series methodology to identify three key patterns. First, economic freedom in China has exhibited a sustained increase since the 1980s. Second, by contrast, liberal democracies in advanced economies show a decline in economic freedom since the turn of the millennium. Third, evidence from party manifestos indicates a rising prevalence of de-growth-oriented political preferences in democratic economies over the past decade. As a potential avenue for future research, we propose framing economic freedom as a public good, in line with Hayekian principles. Overall, the study provides a descriptive foundation of the relationship between economic freedom, political preferences, and economic performance. Full article