Writing and typing are fundamental tasks in academic and professional settings, yet prolonged engagement often contributes to musculoskeletal disorders (MSDs) of the wrist, forearm, and neck.Handwriting techniques, learned early in life and maintained throughout adulthood, play a critical role in shaping ergonomic outcomes.The Palmer handwriting method, developed in the early 20th century to emphasize whole-arm rather than finger-centric movement, has largely fallen out of practice with the rise of typewriting and digital communication.This study investigates writing methods as one the understudied root causes of musculoskeletal disorders.The study compares muscle fatigue across three writing methods: traditional handwriting, typing, and the Palmer method using surface electromyography (sEMG).Twenty-four healthy participants performed standardized 10-minute tasks in each method, followed by fatigue assessments of the wrist, forearm, and neck.Results show that the Palmer method produced the lowest levels of muscle fatigue and the fastest muscle activation, followed by typing, while traditional handwriting generated the highest fatigue and slowest activation.These findings highlight the Palmer method as the most ergonomically efficient approach in terms of muscles fatigue and muscle activation pattern that can induce musculoskeletal disorders in the long term.The study provides evidence-based recommendations for promoting healthier writing practices and suggests that reintroducing ergonomic techniques such as the Palmer method could support high percentage of people through reducing fatigue and the risk of MSDs among students, office workers, and professionals engaged in prolonged writing tasks.

This work studied a new advancement in solar distillation that combines altered modified stepped solar stills (STSSs) with 3 novel features: STSS with vertical corrugated wick SS (MSTSS-VCWSS), MSTSS with finned wick absorber (MSTSS-FWA) and paraffin wax containing silver nanoparticles (PCM-Ag-NPs).The rising water issue caused by population increase and loss of freshwater resources was the driving force behind the research.According to experimental data, the highest freshwater production was obtained for MSTSS-FWA with VCWSS and PCMs-Ag, where the combined productivity of the MSTSS-FWA+VCWSS+ PCMs-Ag reached 11950 ml/m/d, representing a substantial 273% increase over conventional SS.Water costs $0.028 per lire for CSS and $0.011 per liter for MSTSS-FWA+VCWSS+ PCMs-Ag.

This study aims to develop a system dynamics model for halal supply chain traceability and food safety based on Blockchain and Internet of Things (IoT) technology.This approach addresses the lack of transparency, efficiency, and trust in the food supply chain.The model is constructed using primary and secondary data (primarily from Indonesia to facilitate the simulation process), simulated using Vensim PLE, and validated through behavioral, structural, extreme, and parameter tests.This study developed three scenarios: increased growth efficiency, increased investment, and increased farmer storage capacity.During the simulation period, blockchain and IoT implementation increased food availability for consumption by 5% and reduced fresh food inventory losses by 3%.The scenario of increasing farmer storage capacity showed a 10% increase in food availability and reduced fresh food inventory losses by 4% compared to the initial model.Thus, the proposed approach helps maximize food availability and reduce fresh food inventory losses more optimally.

In our work, the influence of the printing speed, the raster angle, the layer thickness, and the short carbon fiber-reinforced composites based on PLA as matrixon the thermal, mechanical, and microstructural properties were analyzed.These composites were printed using as 3D printing process the fused deposition modeling (FDM).To ensure the reliability of the experimental results, three measurements were elaborated on each tensile and micro-hardness test condition and the average values are used.Standard deviation (SD) was calculated to provide statistical validation of our experimental results.Based on tensile measurements, the raster angle =0considerablyincreases stiffness and strength, mainly in thinner layers (Th=0.3mm).In fact, increasing Th from 0.3mm to 0.4mm leads to a significant improvement in the stiffness of the printed parts, with the increase of Young's modulus (E) reaches up to 250%.Additionally, the higher printing speed increases strength of printed composites whereas decreasing their stiffness.In fact, a higher printing speed increases the strength of the printed composites, with the ultimate tensile strength (UTS) increasing by 90%, whereas it decreases their stiffness, with the Young's modulus (E) dropping by 15%.Furthermore, adding short carbon fibers into the polymer matrix significantly advancesthe stiffness and the strength of printed composites (SCFR-PLA) compared to printed polymer (PLA).However, this improvementis accompanied with a decrease of ductility of printed parts.These results provide appreciated understandings into optimizing 3D printing parameters for improved properties of printed composites in various engineering applications.Furthermore, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM) were developed to analyze respectively the thermal behavior of printed composites (SCFR-PLA) and the relationship between porosity of printed partsand theirmechanical properties.

This research investigates the effect of silicon dioxide nanopowder, with particle sizes ranging from 20 to 30 nm, on the fatigue durability of carbon fiber/polyester composites.A series of fatigue experiments were conducted to assess the lifespan of the samples, which were created using varying amounts of nano silicon dioxide (SiO) at weight percentages of 0.16%, 0.20%, and 0.24%, while maintaining a carbon fiber weight fraction of 55%.The study details the properties of the composite material based on these different weight percentages.The experimental results indicated that reinforcing the carbon fiber/polyester composite with silicon dioxide nanoparticles improved its fatigue life across various ratios.The fatigue tests were conducted using a bending alternating method with fully reversed loading (R = -1).The specimens, with a thickness of 7 mm, were tested in a room temperature environment.Fatigue life was evaluated at three distinct stress amplitudes: the first level comprised 78.43, 92.98, and 106.16MPa; the second level included 87.65, 103.91, and 118.64 MPa; and the third level featured 98.59, 116.89, and 133.45 MPa.The fatigue behavior was described using the Basquin equation.The results showed that, at a weight fraction of 0.16%, an increase in stress rate of 14.03% resulted in a decrease in cycles of 12.43% at the first level and 11.34% at the second level.A similar stress rate reduction at the third level led to a 9.4% decrease in cycles.Higher stress amplitudes significantly shortened life cycles.For the 0.20% additive, an increase in average stress by 14.03% reduced life cycles by approximately 12.43%.Further stress increases at the second level led to an 11.34% decline in cycle count, while the same increase resulted in a 9.35% decrease in cycles.Fatigue evaluations on samples with 0.24% of nanoparticles showed a 14.03% increase in the stress ratio, which consequently resulted in a decrease of fatigue cycles by 7.5% at the first level, 8.3% at the second level, and 9.4% at the third level.This minor change suggests improved durability against failure with the incorporation of 0.24% nano silicon dioxide (SiO) as stress levels increased.Scanning electron microscope (SEM) images of the composite samples at a magnification of 2.0 kx demonstrate a homogeneous dispersion of nanoparticles within the microstructure, enhancing the mechanical properties of the composites.

This study proposes a framework for an integrated and sustainable photovoltaic (PV)-based system, which aims at improving energy saving in cooling and air conditioning technologies, enhancing industrial productivity, and minimizing grid electricity dependency.The core goal of this study was to achieve efficient energy consumption by integrating PV systems with a thermal storage system (TES), high-temperatures cooling solutions, and a variable refrigerant flow (VRF).The PVsyst software was employed for analyzing the optimum tilt angle of the PV system in Taiz Al-Huban, Yemen, to be at 17.5.The results showed a reduction in annual energy consumption by 24.79 % when PV is combined with VRF and TES, meeting industrial cooling demands, significantly reducing energy use, and lowering carbon emissions.An additional innovation of this system lies in the design of an efficient cooling system to control PV arrays' temperatures at the required levels, sustaining higher efficiency and generalizing it for varied climatic conditions.Another contribution of this study is the economic feasibility analysis, conducted using both Yemeni and global cost parameters, with an extremely short payback period for the Yemeni context at 2.4 years, underscoring the system's effectiveness in industrial applications.Furthermore, a literature gap analysis identified a clear need for continued research into the integration of advanced cooling technologies with PV systems in industrial settings.The proposed sustainable system agrees with the massive efforts required to bring Yemen's energy sector to a safe level, ensuring an uninterrupted power supply, competitive prices, and environmental cleanliness.

In recent times, nano powder mixed electrical discharge machining (NPMEDM) is one of the leading machining processes when applications are based on nano powders.The process is a unique way of machining wherein electrical discharge machining (EDM) is clubbed with nano powders in dielectric fluid.This new combination produces better results and improves the process responses, like material removal and surface roughness, which are very well handled.The intention here is to focus on eliminating the frequent usage of finis hing processes.An experimental work was realized to determine the influence of the machining parameters, namely, flushing pressure (FP), peak current (I), and pulse on time (TON) on the dependent variables, especially on the material removal rate and surface roughness.during the finishing stage, to break through the constraints generated by the conditions of the EDM process.It was found that the lower MRR was achieved at both the higher and lower flushing pressures with nano powder at 0.2 kg/cm and 1 kg/cm, respectively.The optimal flushing pressure with nano powder has been found to be around 0.5 kg/cm and does not significantly influence the material removal rate.At the same time, the use of nano powder in EDM with flushing at optimum value has shown promising results in enhancing surface roughness.Hence, we can state that the flushing pressure (FP), when combined with the nano powder in the dielectric, is significant at its optimal value in the finishing operations in EDM.

This study presents a comprehensive experimental investigation into the static pressure drop behavior across vortex chambers with various aspect ratios, ranging from 1.36 to 22.36.Vortex chambers are essential components in several fluidic systems, including separators, atomizers, and vortex tubes, where efficient pressure drop management is vital for optimal performance.Despite numerous previous studies focusing primarily on medium aspect ratios (~2-3), limited work has been done on understanding the pressure drop characteristics across a broader range of aspect ratios.Using a jet-driven vortex chamber with interchangeable vortex generators and swirlers, experiments were conducted under controlled inlet conditions with varying flow rates and swirl angles (30 and 40), employing air as the working fluid.The Reynolds numbers covered were from 1811 to 2898, and contraction ratios varied over a wide spectrum by adjusting the exit port size.Dimensional analysis was employed to reduce the data into a general form, revealing that the dimensionless pressure drop is a function of the Reynolds number, aspect ratio, and inlet angle.Results show that the experimental data collapse into a single curve for a given contraction ratio, confirming the robustness of the derived non-dimensional formulation.Furthermore, the analysis demonstrates that increasing aspect ratio significantly affects the flow behavior and pressure drop characteristics.The study concludes with a generalized chart that correlates key geometric and flow parameters, offering a valuable design tool for engineers and researchers working on vortex flow systems.This work extends the foundational understanding of vortexinduced pressure drops and provides crucial insights into optimizing vortex chamber geometries for improved energy efficiency and fluid control.

To enhance the stability of the vehicle subjected to a tire blowout, this paper introduces a corrective active steering safety control system to stabilize the vehicle.The vehicle model is represented by a high-fidelity 14 degrees of freedom (DOF) model that is validated using MSC Adams Package.Subsequently, using the single-track bicycle control-oriented model, an active front steering control strategy in the framework of a linear quadratic regulator (LQR) controller combined with a Kalman filter is established and evaluated.To account for the possible driver reactions following the tire blowout accident, a driver model is augmented to the loop.This representation is more realistic in comparison with the open-loop-based controller design approach.The coupled vehicle-driver system is analyzed and integrated with the proposed linear quadratic gaussian (LQG) controller.The simulation results show that the proposed control system can sufficiently stabilize the system in the presence of the external disturbances associated with the tire blowout, as well as the reactions from the driver by means of minimizing the yaw rate triggered by these disturbances during both straight-line and cornering motions.

In order to determine if perforated absorber plates with circular holes of 6 mm and 3 mm diameter, respectively, in the solar collector enhance the performance of a dryer compared to the traditional flat absorber plate, an experimental investigation was conducted under Iraqi climatic conditions to investigate the enhancement of the performance of an indirect solar air dryer system with forced convection.The experiments were conducted in June 2024 at Baghdad city, located at 33.3N latitude.A solar air dryer comprises a solar air collector inclined at 30 towards the south, an electric fan, and a drying chamber.In the present study, the surface of an absorber plate was modified by forming circular holes on the surface of the plate, which contributes to breaking the thermal barrier layer on the plate and thus improving the heat transmission from the hot plate to the air.Modifying the absorption plate results in a heightened thermal efficiency of the solar air collector compared to the traditional flat absorber plate.The results confirmed that the solar collector with a perforated absorption plate enhanced the solar dryer's effectiveness.A perforated plate with a diameter of 3 mm outperformed both the perforated plate with a diameter of 6 mm and the flat absorber plate.Results indicated that using the perforated plate with a diameter of 3 mm resulted in a 50.32% improvement in collector thermal efficiency and a 27% improvement in dryer efficiency when compared with the perforated plate with a diameter of 6 mm and the flat absorber plate.