Search Results (300)

The relationship between trade openness and economic performance has been widely debated and researched during the last several decades. However, the specific influence of trade openness from the perspective of controlling the inflation rate is rarely researched specifically for the Kingdom of Saudi Arabia (KSA). Accordingly, this research paper attempts to test the influence of trade openness on inflation, focusing on KSA. The paper utilizes historical data from 1975 to 2023 and employs the “Autoregressive Distributed Lag (ARDL)” and “Nonlinear Autoregressive Distributed Lag (NARDL)” cointegration techniques to assess the responsiveness of the inflation rate to increased trade openness. The results of the ARDL demonstrated the positive influence that trade openness has on inflation, which is a rejection of Romer’s hypothesis. The findings of the NARDL also rejected Romer’s hypothesis by demonstrating a positive relationship between the positive shocks in trade openness and the inflation rate. Similarly, our results illustrated a significant negative impact of domestic industrialization and government expenditure on inflation. Moreover, we found that the inflation rate in KSA is significantly dependent on economic performance. Finally, our findings demonstrated that the natural resource sector is unable to explain the inflationary pressure in KSA significantly. Full article

Flexible inflatable film wings have many functional advantages that traditional fixed rigid wings do not possess, such as foldability, small size, light weight, convenient storage, transportation, and so on. More and more scholars and engineers are paying attention to flexible inflatable wings, which have gradually become a new hot research topic. However, flexible wings rely on inflation pressure to maintain the shape and rigidity of the skin film, and the inflation pressure has a significant influence on the strain deformation and wing bearing characteristics of flexible wing skin film. Here, based on the flexible mechanics theory and balance principle of flexible inflatable film, a theoretical model of structural deformation and internal inflation pressure was constructed, and finite element simulation analysis under different internal inflation pressure conditions was carried out as well. The results demonstrate that the biaxial deformation of flexible wing skin film is closely related to internal inflation pressure, local size, configuration, and film material properties. However, strain deformation along the wingspan direction is quite distinguishing, skin films work under the condition of biaxial plane deformation, and the strain deformation of the spanning direction is obviously higher than that of the chord direction, which all increases with internal inflation pressure. Therefore, it is necessary to pay more attention to bearing strain deformation characteristics to meet the bearing stiffness requirements, which could effectively provide a theoretical reference for the structural optimization design and inflation scheme setting of flexible inflatable wings. Full article

The paper presents results of experimental research on tyre–road contact stress distributions, measured indoors for a motorsport slick tyre. The triaxial contact stress distributions have been measured using the complex transducer containing a transversal array of 30 sensing pins covering the entire contact patch width. Wheel displacement in the longitudinal direction was measured using a rotary encoder. The parameters allocated for the experimental programme have included different values of tyre inflation pressure, vertical load, camber angle and toe angle. All measurements were performed at low longitudinal speed in free-rolling conditions. The influence of tyre functional parameters on the contact patch shape and size has been discussed. The stress distributions on each orthogonal direction are presented in multiple formats, such as 2D graphs in which the curves show the stresses measured by each sensing element versus contact length; surfaces with stress values plotted as vertical coordinates versus contact patch length and width; and colour maps for stress distributions and orientations of shear stress vectors. The effects of different parameter types and values on stress distributions have been emphasised and analysed. Furthermore, the magnitude and position of local extreme values for each stress distribution have been investigated with respect to the above-mentioned tyre functional parameters. Full article

Pneumatic artificial muscles (PAMs) consist of an elastomeric bladder wrapped in a Kevlar braid. When inflated, PAMs expand radially and contract axially, producing large axial forces. PAMs are often utilized for their high specific work and specific power, as well as their ability to produce large axial displacements. Although the axial behavior of PAMs is well studied, the radial behavior has remained underutilized and is poorly understood. Modeling was performed using a force balance approach to capture the effects that bladder strain and applied axial load have on the anchoring force. Radial expansion testing was performed to validate the model. Force due to anchoring was recorded using force transducers attached to sections of aluminum pipe using an MTS servo-hydraulic testing machine. Data from the test were compared to the predicted anchoring force. Radial expansion in large-diameter (over 50.8 mm) PAMs was then used in worm-like robots to create anchoring forces that allow for a peristaltic wave, which creates locomotion through acrylic pipes. By radially expanding, the PAM presses itself into the pipe, creating an anchor point. The previously anchored PAM then deflates, which propels the robot forward. Modeling of the radial expansion forces and anchoring was necessary to determine the pressurization required for proper anchoring before slipping occurs due to the combined robot and payload weight. Full article

The Tunnel Boring Machine (TBM) method has gained attention as an eco-friendly tunneling technique, effectively reducing noise, vibration, and carbon emissions compared to conventional blasting methods. However, ground settlement and volume loss are inevitable during TBM excavation due to the deformation of the surrounding ground, which may even lead to ground collapse in severe cases. In this study, a Shield TBM model, validated using field data, was employed to perform numerical analyses on parameters such as tunnel diameter, ground elastic modulus, face pressure, and backfill pressure. Based on the simulation results, the influence of each parameter on settlement was evaluated, and a predictive model for estimating maximum settlement was developed. The proposed model was statistically validated using p-value assessment, variance inflation factor (VIF), coefficient of determination (R²), and residual analysis. Furthermore, the prediction model showed high agreement with the field data, yielding a prediction error of 8.25%. This study emphasizes the applicability of verified numerical modeling for accurately predicting ground settlement in Shield TBM tunneling and provides a reliable approach for settlement prediction under varying construction conditions. Full article

The contact characteristics of radial tires are crucial for optimizing stress distribution, deformation, and wear. The non-uniform contact stress behavior induced by complex tread patterns remains under-explored in existing tire mechanics research. Taking the 205/50R17 radial tire as a representative case, a reverse modeling approach was employed to develop an accurate finite element model for tires incorporating intricate tread pattern features. The fidelity of the proposed tire simulation model was confirmed utilizing high-precision contour profiling techniques. The impact of diverse usage conditions and design parameters on the tire outer profile and ground contact characteristics under static and free-rolling states was analyzed. Experimental observations demonstrate that the increased inflation pressure leads to a proportional decrease in contact area. Under incremental vertical loading, the contact patch develops progressively into a saddle-shaped geometry featuring elevated shoulder regions and a recessed central zone. Increasing the belt angle compromises its hoop-stiffening function, thereby inducing elliptical contact patch geometry. Larger design diameters compromise contact length symmetry in shoulder regions. Variation in shoulder thickness at 85% of the tread width results in a significant difference in contact length between the left and right tread blocks in the rolling state. This work enables refinement strategies for both tread configurations and tire dimensional designs in industrial applications. Full article

This study explores how energy price inflation affects supply chain pressures under different levels of political uncertainty. Using local projection impulse–response functions, we examine the effects of oil price shocks under two regimes: one with above-average levels of political uncertainty and another with below-average uncertainty. While previous research has focused on the direct macroeconomic impacts of oil price shocks, particularly on firm costs and consumer prices, this study highlights the effects of these shocks on supply chain disruption as a whole. Our findings indicate that heightened political uncertainty significantly amplifies the impact of oil price shocks on supply chain pressures, causing notable and persistent disruptions. Conversely, when political stability is high, the response of supply chains to the same shocks is minimal, suggesting that a stable political environment fosters greater resilience in supply chains. Full article

Background: Ultrasound-based assessment of the inferior vena cava (IVC) is a widely used, non-invasive tool for estimating volume status and central venous pressure (CVP) in critically ill patients. However, elevated intra-abdominal pressure (IAP) may distort IVC measurements, reducing the accuracy of CVP estimation. This study aimed to quantify the effect of varying IAP on IVC diameters and evaluate the accuracy of ultrasound-based CVP predictions under such conditions. Methods: A prospective study was conducted including two groups of adult critically ill patients: one with spontaneously elevated IAP due to ascites (n = 36), undergoing stepwise pressure reduction via paracentesis, and one with normal baseline IAP (n = 30), undergoing stepwise pressure elevation using an abdominal belt with an inflatable balloon. End-inspiratory and end-expiratory IVC diameters and CVP were repeatedly measured at different IAP levels. Agreement between predicted and measured CVP was assessed using Gwet’s agreement coefficient, and a correction model for IVC diameters was developed based on IAP categories. Results: Increasing IAP led to a progressive reduction in both inspiratory and expiratory IVC diameters, while CVP showed no consistent trend. Predictive accuracy declined with rising IAP, with Gwet’s agreement coefficient decreasing from 0.851 (95 percent confidence interval: 0.750–0.952) at normal pressure to 0.392 (95 percent confidence interval: 0.141–0.642) at IAP above 25 mmHg. Applying the correction model improved prediction accuracy, with Gwet’s agreement coefficient increasing to 0.749 (95 percent confidence interval: 0.589–0.908) at the highest IAP category. Conclusions: Elevated IAP significantly alters IVC diameters and reduces the reliability of ultrasound-based CVP estimation. A correction model based on IAP improves predictive accuracy and may enhance volume assessment in critically ill patients. Further validation is warranted. Full article

Improper car tire pressure affects dynamics, fuel economy, and driver safety. Current central tire inflation systems (CTISs) regulate tire pressure relative to its reference value. However, the current CTIS is limited in its automation, as the system requires the loading of present conditions and the manual input of terrain conditions. Therefore, the system lacks intelligent components which would increase its efficiency. Adding a terrain recognition feature to the current CTIS technology, the tire pressure management system (TPMS) described in this paper enhances the capability to adjust to the ideal tire pressure according to the terrain condition. In this study, we integrate a terrain recognition component which uses a convolutional neural network (CNN), specifically, ResNet-18, into the TPMS to classify and detect terrain conditions and apply the correct pressure level. A one-tire terrain-based TPMS model was developed through system integration. The system was tested under flat, uneven, and soft terrain conditions. The CNN model demonstrated 95% accuracy in classifying the chosen terrains, with demonstrated adaptability to nighttime environments. Inflation and deflation tests were conducted at varying speeds and terrains, and the results showed longer inflation times at higher pressure ranges, while deflation times remained consistent regardless of pressure range. A negligible impact on inflation and deflation speed was observed at speeds below 15 km/h. Instantaneous response time between the microcontrollers increases efficiency in the overall CTIS process. Full article

Incorrect vehicle tire pressure affects vehicle dynamics, fuel efficiency, and driver safety across different terrain conditions. The current central tire inflation system (CTIS) alleviates this issue by adjusting the tire pressure to a predetermined reference level. However, the existing CTIS only adjusts the pressure based on load conditions through manual input for terrain types and lacks advanced intelligence for optimal automation. Integrating the recognition result of terrain conditions enables real-time adjustments of tire pressure and enhances driving performance and efficiency. This study aims to integrate the terrain recognition component using a convolutional neural network (CNN) by reviewing previous terrain-detection models. The CTIS was enhanced to classify and detect terrain conditions and apply the correct tire pressure level. We employed a systematic literature review (SLR) to assess the development procedures for integrating the intelligent component with the basic CTIS. ResNet-18 was used as the most appropriate CNN model to classify the terrain conditions on a gathered local dataset. A single-wheel testbed using the enhanced CTIS is appropriate for laboratory testing and system integration tests. Full article

Amidst a period of sustained inflation and rising living costs, food insecurity is a growing concern in Australia and is correlated with poor diet quality and increased rates of non-communicable diseases. Currently there is a gap in knowledge of the impact of increasing cost-of-living pressures on the affordability of a healthy diet. As affordability plays a key role in food security, this cross-sectional study aimed to examine the costs, affordability, and differential of habitual (unhealthy) and recommended (healthy) diets within the Illawarra region of Australia and compare results to 2022 findings. The Healthy Diets Australian Standardised Affordability and Pricing tool was applied in six locations in the Illawarra, with two randomly selected each from a low, moderate, and high socioeconomically disadvantaged area. Costs were determined for three reference households: a family of four, a single parent family, and a single male. Affordability was determined for the reference households at three levels of income: median gross, minimum-wage, and welfare dependent. Data was compared to data collected in 2022 using the same methods and locations. Recommended diets cost 10.3–36% less than habitual diets depending on household type, but remained unaffordable for welfare dependant households and family households from socioeconomically disadvantaged areas, where diets required 25.5–45.9% of household income. Due to income increases, affordability of both diets has marginally improved since 2022, requiring 0.5–4.8% less household income. This study provides updated evidence that supports the urgent need for policies, interventions, and monitoring to widely assess and improve healthy diet affordability and decrease food insecurity rates. Possible solutions include increasing welfare rates above the poverty line and utilising nudge theory in grocery stores. Full article

Soft pneumatic robot-arm end-effectors can facilitate adaptive architectural fabrication and building construction. However, conventional pneumatic grippers often suffer from air leakage and tear, particularly under prolonged grasping and inflation-induced stress. To address these challenges, this study suggests an enhanced anthropomorphic gripper by integrating a pre-stressed reversible mechanism (PSRM) and a novel self-healing material (SHM) polyborosiloxane–Ecoflex™ hybrid polymer (PEHP) developed by the authors. The results demonstrate that PSRM finger grippers can hold various objects without external pressure input (12 mm displacement under a 1.2 N applied), and the SHM assists with recovery of mechanical properties upon external damage. The proposed robotic hand was evaluated through real-world construction tasks, including wall painting, floor plastering, and block stacking, showcasing its durability and functional performance. These findings contribute to promoting the cost-effective deployment of soft robotic hands in robotic construction. Full article

Effective coordination between fiscal and monetary policy is crucial for macroeconomic stability, yet achieving it presents significant challenges due to differing objectives and institutional setups. This study evaluates the strategic interaction between fiscal and monetary authorities in Hungary from 2013 to 2023, employing the Nash equilibrium framework under the assumption of non-cooperative behavior. By modeling the authorities as independent players optimizing distinct payoff functions based on key economic indicators (interest rates, government spending, inflation, output gap, fiscal deficit, and public debt), the analysis estimates the best response strategies and computes the resulting Nash equilibrium. The key findings reveal persistent deviations between actual policies and the computed equilibrium strategies. Specifically, actual fiscal policy was consistently more expansionary (average actual deficit −2.6% to 7.6% GDP vs. equilibrium recommendations ranging from 8.5% surplus to −3.0% deficit) than the Nash equilibrium indicated, particularly during periods of economic growth. Monetary policy often lagged in equilibrium recommendations, maintaining low interest rates (e.g., 0.9% actual vs. 11.5% equilibrium in 2019) before implementing sharp increases (13% actual vs. approx. 3.5–3.8% equilibrium in 2022–2023) that significantly overshot the equilibrium. These misalignments underscore potential suboptimal outcomes arising from independent policymaking, contributing to increased public debt and heightened inflationary pressures in the Hungarian context. This study highlights the potential benefits of aligning policies closer to mutually consistent strategies, suggesting that improved coordination frameworks could enhance macroeconomic stability, offering insights relevant to Hungary and similar economies. Full article

We investigated the impact of sustainable banking practices on bank stability in the Nigerian banking sector. We focused on data from 2012 to 2022, which were extracted from the balance sheets of deposit money banks in Nigeria. We employed the Dynamic Ordinary Least Squares (DOLS) estimator with E-Views to analyze the data. Our findings show that environmental emissions and waste reduction have minimal effects on bank assets, capital adequacy, and liquidity, though they do not directly cause financial instability. Investments in environmental innovation reduce asset growth and increase liquidity constraints but lower non-performing loans, emphasizing a trade-off between sustainability and stability. Environmental resource use efficiency remains neutral regarding asset stability and capital adequacy but poses liquidity challenges. Social welfare investments have little impact on asset growth and profitability, potentially reducing financial stability. Human resource development improves capital adequacy and liquidity strengthening bank stability, while community investments aid societal growth but create liquidity pressures. Macroeconomic factors like GDP growth and inflation are significant, yet economic growth does not always increase bank assets, whereas inflation increases non-performing loans. Sustainable banking in Nigeria is evolving; therefore, there is a need for robust regulation, financial incentives for compliance, a high level of awareness, and alignment between banking operations and sustainability principles. Full article

As agricultural tractors function under various soil and environmental conditions, optimising their design and paraameter settings for enhanced traction performance is essential for maximising their operational efficiency. This study aimed to assess the traction capabilities of standard tractors, ensuring effective operations even under highly demanding conditions. A traction load measurement system was refined to collect performance data, and standardised tests were conducted on a concrete track to evaluate key traction metrics. The analysis considered drawbar pull, traction force, travel reduction (slip), and net traction ratio. Two tractors from the same model series, featuring similar design characteristics but differing in engine power, were compared. Three primary parameters—tractor mass, tyre pressure, and engine power—were evaluated across six distinct operating conditions. Results recorded at forward speeds below 6 km/h indicated that lower tyre pressure led to an increased net traction ratio due to the enhanced drawbar pull. Additionally, an increase in tractor mass contributed to a higher drawbar pull, which, in turn, improved traction force across all speed ranges. The maximum traction force was not significantly affected between 66 kW and 86 kW tractors at speeds up to 4 km/h. Meanwhile, the traction force remained high up to velocities of 6 km/h in the 86 kW tractor. The efficiency (i.e., the ratio between measured and declared power) varied between 64% and 70% for the 66 kW tractor and between 70% and 74% for the 86 kW tractor. The travel reduction was mainly affected by the power of the tractor. The slip caused a reduction close to 4 and 6 km/h for the 66 kW and 86 kW agricultural tractors, respectively. Overall, the proper adjustment of tractor parameters significantly impacted their traction performance, and the findings provide valuable insights for improving tractor designs and field applications. Full article