Search Results (807)

This study aims to clarify the longitudinal flexural cracking characteristics in hogging moment regions and propose a practical calculation method for the cracking load and ultimate bearing capacity for a steel–GFRP strips–UHPC composite deck structure. The longitudinal flexural behavior of two steel–GFRP strips–UHPC composite beams in the hogging moment region is determined through a three-point loading test method. Their failure modes and mechanisms, crack propagation and distribution characteristics are analyzed considering the influence of the reinforcement ratio. The variation of the law of mid-span displacement, maximum crack width, strains and interface slip with load are discussed. Calculation methods for the cracking load and ultimate bearing capacity of steel–GFRP strips–UHPC composite beams are proposed. The results show that with the increase of the reinforcement ratio, the cracking load and ultimate bending capacity are improved by 11.1% and 6.0%, respectively. However, the development of cracks is inhibited, as the crack width, average crack spacing and strain of the reinforcement bars are reduced as the reinforcement ratio increases. The maximum crack width changes linearly with the load as it is less than 0.2 mm. The theoretical cracking load and ultimate bearing capacity of the composite beams considering the tensile contribution of UHPC achieve good agreement with the experimental values. Full article

Circular deep excavations, characterized by their symmetrical geometry, are commonly employed in constructing foundations for large-span suspension bridges and as launching shafts for shield tunneling. However, the mechanical behavior of such excavations under asymmetric surface surcharge remains inadequately understood due to a paucity of relevant investigations. This study addresses this knowledge gap by establishing a three-dimensional finite element model (3D-FEA) based on the anchor deep excavation project of a specific bridge. The model is utilized to investigate the influence of asymmetric surcharge on the forces and deformations within the supporting structure. The results show that both the internal force and displacement cloud diagrams of the support structure exhibit asymmetric characteristics. The distribution of displacement and internal forces has spatial effects, and the maximum values all occur in the areas where asymmetric loads are applied. The maximum values of the displacement, axial force, and shear force of underground continuous walls increase with the increase in the excavation depth. The total displacement curves all show the feature of a “bulging belly”. The maximum displacement is 13.3 mm. The axial force is mainly compression, with a maximum value of −9514 kN/m. The maximum positive and negative values of the shear force are 333 kN/m and −705 kN/m, respectively. The bending moment diagram of different monitoring points shows the characteristics of “bow knot”. The maximum values of the positive bending moment and negative bending moment are 1509.4 kN·m/m and −2394.3 kN·m/m, respectively. The axial force of the ring beam is mainly compression, with a maximum value of −5360 kN, which occurs in ring beams 3, 4, and 5. The displacement cloud diagram of the support structure under symmetrical loads shows symmetrical characteristics. Under different load conditions, the displacement curve of the diaphragm wall shows the characteristics of “bulge belly”. The forms of loads with displacements from largest to smallest at the same position are as follows: asymmetric loads, symmetrical loads, and no loads. These findings provide valuable insights for optimizing the structural design of similar deep excavation projects and contribute to promoting sustainable urban underground development. Full article

This study investigates the impact of cultural openness on intertemporal consumption behavior in the Middle East and North Africa (MENA) region, using panel data from 14 countries spanning 2010 to 2022. Unlike prior research that primarily focused on lifestyle shifts or product preferences, this study explores how cultural globalization influences the trade-off between present consumption and future savings, as captured by the consumption-to-savings ratio (LCESR). Cultural openness is operationalized using the Cultural Globalization General Index (LCGGI), and its effect is analyzed alongside key control variables including Internet penetration, real GDP per capita, inflation, and tourism. To address endogeneity and unobserved heterogeneity, this study employs the system Generalized Method of Moments (GMM) estimator, supported by robustness check models. The findings reveal a significant positive relationship between cultural openness and LCESR in both the short and long run, indicating that increased exposure to global cultural flows enhances consumption tendencies in the region. Internet penetration and inflation negatively affect saving behavior, while GDP per capita shows a positive effect. Tourist arrivals exhibit limited influence. This study also highlights the importance of historical consumption behavior, as the lagged dependent variable strongly predicts the current LCESR. Robustness checks confirm the consistency of the results across all models. These insights suggest that cultural openness, digital infrastructure, and macroeconomic stability are pivotal in shaping consumption/saving patterns. The results carry important implications for financial education, digital consumption governance, and cultural policy strategies in the MENA region and similar emerging markets undergoing rapid cultural integration. Full article

This study investigates the impact of geopolitical risk, firm characteristics, and macroeconomic variables on the performance of non-financial firms listed on the Egyptian Stock Exchange. The study analyzes a panel dataset consisting of 182 Egyptian firms over the period 2014–2023. Using the panel Generalized Method of Moments (GMM) regression technique, the study examines the effect of geopolitical risk on the return on assets. This study controls for firm characteristics such as liquidity, leverage, and growth opportunities and controls for macroeconomic variables such as inflation and GDP. This empirical evidence investigates the moderating role of FinTech on such relationship. The results reveal a significant and negative relationship between geopolitical risk and firms’ performance. Liquidity, growth opportunities, and inflation show positive and significant impacts. In contrast, leverage and GDP demonstrate significant negative relationships. Remarkably, FinTech moderates the relationship significantly and positively. Therefore, investors ought to proceed with prudence when positioning cash within elevated political volatility. The significant positive moderating effect of FinTech on this connection provides a vital strategic insight: enterprises with enhanced FinTech integration may demonstrate increased resilience to geopolitical shocks. Full article

Achieving sustainable economic growth requires a careful balance between public debt accumulation and the macroeconomic stability necessary for long-term development. While public debt can support growth through productive public investment, excessive debt may crowd out private investment, raise borrowing costs, and undermine financial stability, ultimately threatening economic sustainability. In this context, the quality of institutions plays a pivotal moderating role by fostering responsible debt management and ensuring that debt-financed investments contribute to sustainable development. In this context, this study investigates the relationship between public debt and economic growth, with a focus on the moderating role of institutional quality (IQ). Utilizing an unbalanced panel of 115 countries over the period from 1996 to 2021, this study tests the hypothesis that robust institutional frameworks mitigate the negative impact of public debt on economic growth. To address potential endogeneity, this study employs the dynamic system Generalized Method of Moments (GMM) estimation technique. The results reveal that, although the direct effect of public debt on economic growth is negative, the interaction between public debt and IQ yields a positive influence. Furthermore, the results indicate the presence of a threshold beyond which public debt begins to exert a beneficial effect on economic growth, whereas its impact remains adverse below this threshold. These findings underscore the critical importance of sound debt management strategies and institutional development for policymakers, suggesting that effective government governance is essential to harnessing the potential positive effects of public debt on economic growth. Full article

The intentional yaw offset of wind turbines has shown potential to redirect wakes, enhancing overall plant power production, but it may increase fatigue loading on turbine components. This study analyzed fatigue loads on the NREL 5 MW reference wind turbine under varying yaw offsets using blade element momentum theory, dynamic blade element momentum, and the converging Lagrange filaments vortex method, all implemented in OpenFAST. Simulations employed yaw angles from −40° to 40°, with turbulent inflow generated by TurbSim, an OpenFAST tool for realistic wind conditions. Fatigue loads were calculated according to IEC 61400-1 design load case 1.2 standards, using thirty simulations per yaw angle across five wind speed bins. Damage equivalent load was evaluated via rainflow counting, Miner’s rule, and Goodman correction. Results showed that the free vortex method, by modeling unsteady aerodynamic forces, yielded distinct differences in damage equivalent load compared to the blade element method in yawed conditions. The free vortex method predicted lower damage equivalent load for the low-speed shaft bending moment at negative yaw offsets, attributed to its improved handling of unsteady effects that reduce load variations. Conversely, for yaw offsets above 20°, the free vortex method indicated higher damage equivalent for low-speed shaft torque, reflecting its accurate capture of dynamic inflow and unsteady loading. These findings highlight the critical role of unsteady aerodynamics in fatigue load predictions and demonstrate the free vortex method’s value within OpenFAST for realistic damage equivalent load estimates in yawed turbines. The results emphasize the need to incorporate unsteady aerodynamic models like the free vortex method to accurately assess yaw offset impacts on wind turbine component fatigue. Full article

This study explores the impact of growth opportunities on the capital structure of South African banks, utilising panel data from registered banking institutions covering the period from 2014 to 2023. While a substantial body of literature examines the relationship between growth prospects and corporate leverage, limited attention has been paid to this interaction within the banking sector, particularly in emerging economies. By employing the dynamic panel Generalised Method of Moments (GMM) estimator to address endogeneity concerns, the analysis reveals a statistically significant positive relationship between growth opportunities and both the total debt ratio (TDR) and the long-term debt ratio (LTDR). In contrast, a significant negative association is found between growth opportunities and the short-term debt ratio (STDR). The findings suggest that banks with stronger growth prospects are more inclined to utilise long-term financing, possibly reflecting shareholder preferences for institutions with favourable future outlooks and lower refinancing risks. These results highlight the importance of aligning capital structure decisions with an institution’s growth trajectory, while indicating that this relationship shifts depending on the maturity of the debt considered. This study contributes to the existing literature by contextualising capital structure decisions within the framework of growth opportunities. Structure theory within the context of the banking sector in a developing market offers practical insights for strategic financial planning and regulatory policy. Full article

Bank operations are contingent upon investor confidence, particularly during periods of economic distress. If investor confidence drops, a bank faces difficulties obtaining money, higher borrowing costs, and lower stock values. Non-performing loans (NPLs) potentially jeopardize a bank’s long-term viability and short-term profitability, and investors are naturally wary of institutions that pose a high credit risk. The purpose of the study was to explore how non-performing loans influence investor confidence in banks. A purposive sampling technique was used to identify 253 New York Stock Exchange banks in the Thomson Reuters Eikon DataStream that satisfied all the inclusion and exclusion selection criteria. The Common Correlated Effects Mean Group (CCEMG) and Generalized Method of Moments (GMM) models were used to analyze the data, providing insight into the relationship between the variables. The study discovered that NPLs had a negative and significant influence on price–earnings (P/E) and price-to-book value (P/B) ratios. Furthermore, the bank’s age was found to have a positive and significant relationship with the P/E and P/B ratio. The moderating relationship between NPLs and bank age was found to have a negative and significant influence on price–earnings (P/E) and price-to-book value (P/B) ratios. The findings underscore the importance of asset quality and institutional reputation in influencing market perceptions. Bank managers should focus on managing non-performing loans effectively and leveraging institutional credibility to sustain investor confidence, particularly during financial distress. Full article

Collar monopile foundation is a new type of offshore wind power foundation. This paper explores the horizontal bearing performance of collar monopile foundation in saturated cohesive soil through a combination of physical experiments and numerical simulations. After analyzing the deformation characteristics of the pile–soil system under horizontal load through static load tests, horizontal cyclic loading tests were conducted at different cycles to study the cumulative deformation law of the collar monopile. Based on a stiffness degradation model for soft clay, a USDFLD subroutine was developed in Fortran and embedded in ABAQUS. Coupled with the Mohr–Coulomb criterion, it was used to simulate the deformation behavior of the collar monopile under horizontal cyclic loading. The numerical model employed the same geometric dimensions and boundary conditions as the physical test, and the simulated cumulative pile–head displacement under 4000 load cycles showed good agreement with the experimental results, thereby verifying the rationality and reliability of the proposed simulation method. Through numerical simulation, the distribution characteristics of bending moment and the shear force of collar monopile foundation were studied, and the influence of pile shaft and collar on the horizontal bearing capacity of collar monopile foundation at different loading stages was analyzed. The results show that as the horizontal load increases, cracks gradually appear at the bottom of the collar and in the surrounding soil. The soil disturbance caused by the sliding and rotation of the collar will gradually increase, leading to plastic failure of the surrounding soil and reducing the bearing capacity. The excess pore water pressure in shallow soil increases rapidly in the early cycle and then gradually decreases with the formation of drainage channels. Deep soil may experience negative pore pressure, indicating the presence of a suction effect. This paper can provide theoretical support for the design optimization and performance evaluation of collar monopile foundations in offshore wind power engineering applications. Full article

This study investigates the response of laterally loaded pile foundations embedded in sloping beds under scour conditions, which is vital for the design and stability of coastal and offshore infrastructure like sea-crossing bridges, offshore wind turbines, and wharves. While previous studies have focused on scour-affected pile performance in horizontal beds, this research expands the scope by incorporating sloped beds and corresponding scour effect, which are common in coastal and offshore environments. A three-dimensional finite element model was established to evaluate the pile foundation’s lateral load-bearing capacity under different slope and scour conditions, according to preceding flume tests on the mechanism of local scour around a pile in sloping bed. The results indicate that the lateral response of the pile is significantly influenced by the seabed slope and scour depth. A negatively inclined seabed weakens the interaction between the pile and the surrounding sediment, thereby reducing the lateral bearing capacity and bending moment. As the scour depth increases, the support provided by the soil further weakens, intensifying the reduction in lateral resistance. This effect is particularly pronounced for steep negative slopes, where the combined impact of slope and scour has a more significant detrimental effect. Full article

Friedrich Nietzsche can be an awkward topic for classicists and ancient philosophers, especially since an important part of his heavily critical philosophy begins as a reaction to, and critique of, his contemporary classical scholarship with which he was intimately familiar, being one of the most impressive ‘products’ of its development. Nietzsche was a thinker who in many ways turned the prevalent opinions about Greeks and contemporaries upside down, challenging his predecessors and successors with provocative readings of some of the most cherished philosophies in Western culture. This essay examines Nietzsche’s treatment of sophists—an important group of intellectuals whose reception had suffered greatly under the devastating judgement of Plato and Aristotle. While recent scholarship frequently regards sophists as philosophers, Nietzsche’s contemporaries were generally extremely dismissive of this group and regarded them in negative light as illegitimate thinkers and opponents to their contemporary ‘true’ philosophers (i.e., Socrates, Plato, and Aristotle). This paper traces two different moments in Nietzsche’s philosophical output that exhibit closer engagement with the sophists: the ‘early’ Nietzsche regards sophists as innovators in language and style, the ‘late’ Nietzsche sees them as countercultural revolutionaries. Despite the fact that in both stages, sophists are introduced as champions for ideas that are central to Nietzsche’s own philosophical preoccupations (the development of language, the overthrowing of values), his treatment of this group of intellectuals appears at first sight superficial and surprisingly unenthusiastic. The paper will examine our existing sources on Nietzsche’s treatment of the sophists and will suggest, ultimately, that his engagement with them was probably far more complex and multilayered than has been thus far assumed. Full article

This study investigates the relationship between overconfidence and meme stock valuation, drawing on panel data from 28 meme stocks listed from 2019 to 2024. The analysis incorporates key financial indicators, including Tobin’s Q ratio, market capitalization, return on assets, leverage, and volatility. A range of overconfidence proxies is employed, including changes in trading volume, turnover rate, changes in outstanding shares, and alternative measures of excessive trading. We observe a significant positive relationship between overconfidence (as measured by changes in trading volume) and firm valuation, suggesting that investor biases contribute to notable pricing distortions. Leverage has a significant negative relationship with firm valuation. In contrast, market capitalization has a significant positive relationship with firm valuation, implying that meme stock investors respond to both speculative sentiment and traditional firm fundamentals. Robustness checks using alternative proxies reveal that turnover rate and changes in the number of shares are negatively related to valuation. This shows the complex dynamics of meme stocks, where psychological factors intersect with firm-specific indicators. However, results from a dynamic panel model estimated using the Dynamic System Generalized Method of Moments (GMM) show that the turnover rate has a significantly positive relationship with firm valuation. These results offer valuable insights into the pricing behavior of meme stocks, revealing how investor sentiment impacts periodic valuation adjustments in speculative markets. Full article

This study aims to analyze the determinants of bank profitability in Angola by employing panel data econometric models, specifically, the Generalized Method of Moments (GMM), to assess the impact of internal and external factors on the financial indicators ROE, ROA, and NIM for the period 2016 to 2023. The results reveal that credit risk, operational efficiency, and liquidity are critical determinants of banking performance. Effective credit risk management and cost optimization are essential for the sector’s stability. Banking concentration presents mixed effects, enhancing net interest income while potentially undermining efficiency. Economic growth supports profitability, whereas inflation exerts a negative influence. The COVID-19 pandemic worsened asset quality, increased credit risk, and led to a rise in non-performing loans and provisions. Reforms implemented by the National Bank of Angola have contributed to strengthening the banking system’s resilience through restructuring and regulatory improvements. The rise of digitalization and fintech presents opportunities to enhance financial inclusion and efficiency, although their success relies on advancing financial literacy. This study contributes to the literature by providing updated empirical evidence on the factors influencing bank profitability within an emerging economy’s distinctive institutional and economic context. Full article

Given the global rise in magnitude and frequency of extreme events due to climate change, accurately determining these values—typically through frequency analysis—is especially important. The article analyzes the particular aspects of three probability distributions of 4 and 5 parameters in flood frequency analysis (FFA) using the L-moments as a parameter estimation method. Aspects regarding the behavior of the five-parameter Wakeby, four-parameter generalized Pareto and four-parameter Burr distributions are highlighted in generating the maximum flow values in the area of low annual exceedance probabilities characteristic of rare and very rare events. After applying these distributions to four case studies, it was found that for the 10,000-year return period event, the relative error between multi-parameter distributions is under 20%—a more than acceptable margin given the extremely low exceedance probability. However, its importance depends on the use of the generated values, which in some cases can lead to excessive costs in establishing structural flood protection measures (urban planning), which can be avoided. It also highlights possible negative consequences (material and human lives) regarding the risk associated with these analyses that can lead to an under-dimensioning of this infrastructure. Full article

Introduction: Pediatric prosthetic knee joints must be appropriately scaled from adult designs to ensure proper gait biomechanics. However, direct dimensional scaling without considering the biomechanical implications may lead to functional discrepancies. This study aimed to evaluate whether using a linear scaling factor can effectively adapt a knee for pediatric use. The study assessed whether such an approach yields a viable pediatric prosthetic knee joint by applying a fixed scaling factor and analyzing the resultant knee geometry. Methods: The linear scaling factor was determined based on the pylon tube diameter, a key constraint in compact pediatric knee design. Given a pediatric pylon diameter of 22 mm, the length of the tibial link was set to 22 mm, yielding a scaling factor of 0.6875 when compared to the adult-sized knee. This scaling factor was used to determine the dimensions of the pediatric four-bar (scaled) knee joint. Static geometric analysis was conducted using GeoGebra^® to model the lower-body segment lengths. The knee joint’s performance was evaluated based on stance and swing phase parameters. These metrics were compared between the scaled knee and a commercial pediatric knee. Results: The geometric analysis revealed that while using the linear scaling factor maintained proportional relationships, certain biomechanical parameters deviated from the expected pediatric norms. The scaled knee achieved a toe clearance of 13.5 mm compared to 19.7 mm in the commercial design and demonstrated a swing-phase heel clearance of 11.6 mm versus 13.3 mm, maintaining negative x/y ratios at heel contact and showing significant stability in push-off moments, while the stance flexion angle remained within an acceptable range. The heel contact and push-off ratios (x/y) were found to be comparable, with the scaled model achieving values of −1.21 and −0.59, respectively. The stance flexion angle measured 10.6°, closely aligning with the commercial reference. Conclusions: Using a linear scaling factor provides a straightforward method for adapting adult prosthetic knee designs to pediatric use. However, deviations in key biomechanical parameters indicate that further experimental study may be required to validate the applicability of the scaled knee joint for pediatric users. Future work should explore dynamic simulations and experimental validations to refine the design further and ensure optimal gait performance. Full article