Variation Of Angle Research Articles

Development, Optimization, and Stability Study of a Yataprasen Film-Forming Spray for Musculoskeletal Pain Management

Yataprasen (YTPS) remedy ethanolic spray, one of the National Thai Traditional Medicine Formulary, is extensively employed in Thai traditional healthcare to manage musculoskeletal pain and inflammation. Despite its widespread use, the quality and stability of the YTPS formulation, critical to its efficacy, safety, and patient adherence, have not been comprehensively studied. This research developed and optimized a film-forming spray (FFS) formulation of YTPS ethanolic extract and conducted a 6-month stability evaluation. The FFS shares similarities with gel formulations, particularly in its ability to form a cohesive, semi-solid film upon application, enhancing localized drug delivery and prolonged contact time. Key physicochemical properties, including density (0.8450–0.9086 g/cm3), pH (4.72–4.95), spray angle (55.58–60.10°), evaporation time (1.04–1.27 min), and theoretical film thickness (7.72–13.97 µm), were analyzed across varying storage conditions. Active components β-amyrin and stigmasterol demonstrated retention rates of 96.78% and 68.22%, respectively, under refrigerated conditions, with degradation rates accelerating at higher temperatures. Significant variations in density, spray angle, film thickness, and stigmasterol concentration were observed. Additionally, the RP-HPLC method was validated for the accurate and precise quantification of the bioactive compounds such as β-amyrin and stigmasterol, demonstrating excellent linearity within a 10–100 µg/mL range for both compounds with excellent linearity R2 > 0.999. The results confirmed that YTPS-FFS exhibits good stability and that the validated HPLC method is reliable for routine quality control. These findings supported the potential of YTPS-FFS formulation as a standardized and effective dosage form for managing musculoskeletal conditions, advancing its role in modernized traditional medicine.

MXene-based multilayered and ultrawideband absorber for solar cell and photovoltaic applications

We proposed the ultrawideband solar absorber using the multisized metal resonator oriented on the top of the multilayered Metal-SiO₂-MXene-MgF₂-Tungsten structure. We have carried out a numerical investigation of this structure for the 100–2500 THz frequency, which covers the infrared, visible, and UV spectra. The proposed solar absorber is numerically investigated for the different physical parameters, such as the height of the layers, unit cell size, and resonator orientation, to identify optimized results for the high absorption capacity. The structure presented in the study shows promise, with an average absorption of 80% over the large frequency spectrum of 100–2500 THz. This structure was also investigated for the variation in oblique incident angle, which showcases the absorption stability up to 60⁰ of the incident angle. We have also reported the comparative analysis for this proposed absorber structure with other designs, demonstrating the absorption efficiency over infrared, visible, and UV spectra. The proposed structure and discrete resonator length can offer a better solution for trapping the different frequency ranges, resulting in high absorption over a wideband frequency. This study can be applied to designing highly efficient parasitic solar absorber structures, which are essential to highly efficient photovoltaic and solar cell design.

Effect of Postoperative Neck-Shaft and Anteversion Angles on Biomechanical Outcomes in Proximal Femoral Osteotomy: An In Silico Study.

Effective surgical planning is crucial for maximizing patient outcomes following complex orthopedic procedures such as proximal femoral osteotomy. In silico simulations can be used to assess how surgical variations in proximal femur geometry, such as femur neck-shaft and anteversion angles, affect postoperative system mechanics. This study investigated the sensitivity of femur mechanics to postoperative neck-shaft angles, anteversion angles, and osteotomy contact areas using patient-specific finite element analysis informed by neuromusculoskeletal models. A sequential neuromusculoskeletal modeling and finite element analysis pipeline was used to simulate postoperative mechanics in three pediatric patients with varying demographic and anatomic features. Nine surgical configurations derived from permutations of the clinical envelope of neck-shaft angles and anteversion angles were simulated for the stance phase of gait. The outcome mechanics assessed were peak von Mises stresses on the bone-implant contact surfaces as well as interfragmentary movement and strain on the osteotomy location. Peak von Mises stress and interfragmentary movement and strain were on average 38% more sensitive to surgical variation in neck-shaft angle compared to anteversion angle. A significant negative correlation was detected between contact area and interfragmentary movement (r = -0.90, p < 0.0001) and strain (r = -0.45, p = 0.017). Overall findings suggest neck-shaft angle significantly influences postoperative femur mechanics and highlight the importance of maximizing contact area to limit interfragmentary motion and foster an optimal mechanical environment for bone healing and callus formation following proximal femoral osteotomy. Between-patient variation in sensitivity to proximal femoral geometry reinforced the importance of patient-specific surgical planning.

Impact of Blade Geometric Parameters on the Specific Cutting Energy of Willow (Salix viminalis) Stems

This article presents a model to estimate the specific energy demand for cutting annual willow stems, considering variations in plant moisture content and sliding-cutting angles. The study involved laboratory tests and statistical analyses. Key parameters were measured for 50 randomly selected annual willow shoots, including total plant weight, leaf weight, stem weight, centre of gravity of the shoot, shoot length, and stem diameter at specified heights: 0, 150, 500, 750, 1000, 1250, 1500, and 2000 mm. Five levels of willow shoot moisture content were evaluated. The study established a cutting force-deformation relationship through strength tests with an accuracy of 1 N, which was subsequently used to calculate shear stress and specific cutting energy. Steel blades with an angle of 30° and sliding-cutting angles of 0°, 15°, 30°, and 45° were used in the study. Ten repetitions were performed for each combination of variable parameters: shoot moisture content and blade sliding-cutting angle. Experimental results were evaluated using analysis of variance (ANOVA), while Duncan’s test was applied to identify and classify groups with homogeneous specific energy values. The developed characterisation offers valuable information for designing shredding units and optimising their operational parameters to reduce energy consumption.

Dust deposition characteristics on photovoltaic arrays investigated through wind tunnel experiments

Optimizing the installation parameters of photovoltaic panels in a photovoltaic array to reduce dust accumulation, thereby enhancing their power generation, is a crucial research topic in the construction of solar power stations in desert regions. Utilizing a series of wind tunnel experiments on a photovoltaic array comprising four equally sized panels, this study assessed how variations in tilt angle, mounting height, spacing, and incoming flow direction influence both the accumulation mass of dust and the particle size distribution in a photovoltaic array. The results indicate that the dust accumulation on the first panel exponential growth with increasing tilt angle, incoming flow angles, and height, while subsequent panels displayed a trend of initial increase followed by a decrease, with a maximum increasing ratio achieved at specific installation configurations, the difference of dust mass on each panel can even be several times. Notably, when the spacing between panels exceeds twice the panel height, the mutual influence on dust deposition becomes negligible, providing a quantifiable threshold for optimal panel spacing. Additionally, significant differences exist in the particle size characteristics of dust in the panel of the array, influenced by the installation parameters of panels and the direction of the incoming flow. This research not only enhances the understanding of dust accumulation in solar energy systems but also offers practical recommendations for optimizing installation strategies, thereby improving the economic viability of solar power stations, particularly in desert regions.

A Parametric study on the effects of winglet cant angle on wing aerodynamics and aeroacoustics

The use of winglet devices is an efficient technique for enhancing aerodynamic performance. This study investigates the effects of winglet cant angles on both the aerodynamics and aeroacoustics of a commercial wing, comparing them to other significant parameters using a parametric analysis. A Full Factorial Design method is employed to generate a matrix of experiments, facilitating a detailed exploration of flow physics, with lift-to-drag ratio (L/D) and the integral of Acoustic Power Level (APL) as the primary representatives of aerodynamic and acoustic performance, respectively. The RANS formulation, along with the Realizable model and the Broadband Noise Source (BNS) model, are utilized to accurately simulate subsonic flows numerically. The study begins by examining the pressure coefficient () and APL distributions at various cant angles near the wingtip and root areas. The matrix of experiments is then analyzed to identify the most influential parameters based on the main effects of inputs and their two-way interactions. The results demonstrate that variations in winglet cant angle significantly alter the distribution of and APL along the span, particularly near the wingtip, and that cant angle strongly impacts overall performance, at times even outweighing atmospheric parameters such as pressure and temperature.

The Effect of Preexisting Fracture Angles on Crack Propagation in Sandstone

The fracture propagation on the rock causes failure and impacts the sustainability time of the structure. As part of the present work, sandstone with the variation of preexisting crack angle was simulated using the extended finite element method (XFEM). The crack propagation on sandstone has a preexisting fracture angle of 30°, 45°, and 60°, with an equivalent crack length. The impact of preexisting fracture angle on the possibility of crack propagation, failure mechanism, and displacement at a critical point of all models was studied. The numerical simulation revealed the crack angle of the model control vibration and its impact on the model’s seismic stability. The XFEM results are validated with reference to those available in the literature. Artificial neural networks (ANNs) are used for prediction by considering the training, testing, and validation process and analyzing prediction errors. The present simulation’s conclusion significantly supports the model’s displacement prediction with no crack propagation occurrence. In addition, by considering the preexisting fracture angle of a model, the load sustainability can be estimated.

Vortex-induced vibration characteristics of twin-box girder section in long-span bridge: A numerical evaluation method

The vortex-induced vibration (VIV) characteristics of twin-box girders are critical in the design of long-span bridges. This study aims to investigate the VIV behavior of a twin-box girder section and to deepen the understanding of the mechanisms underlying VIV. A numerical approach that integrates both free and forced vibration analyses is developed to predict VIV performance. The VIV amplitude is evaluated using the free vibration method within the wind speed range identified by the forced vibration method. Comparisons with wind tunnel test results demonstrate the feasibility of this approach. Meanwhile, flow structure and aerodynamic characteristics of the twin-box girder were analyzed in relation to the VIV mechanism. The results show that flow restrictor plate could effectively suppress vertical VIV at a wind attack angle 0° and reduce the VIV amplitude by 50% at +3°wind attack angle. The central opening slot is identified as a significant factor in inducing VIV, as the upper and lower vortices interact with the airflow passing through the respective sections of the slot. The flow restrictor plates positioned at the upper section of the opening slot cause most upper vortices to shift downstream at wind attack angles of 0° and +3°. This shift results in minimal airflow reflux at the slot, which is crucial for optimizing VIV performance. At a wind attack angle of +3°, the vortices at the lower part of the slot persist, albeit with reduced size. These changes in vortex behavior underscore the sensitivity of vortex formation to variations in wind attack angles.

VISUALIZATION OF COALESCENCE OF TWO LIQUID DROPS OVER A HYDROPHOBIC SURFACE

Coalescence phenomenon of liquid drops of equal and unequal volumes over a hydrophobic surface is reviewed and presented using images from experiments and numerical simulations. Bond number based on the combined volume is in the range of 0.01-0.2. As the drops coalesce, a great variety of interface shapes appear as the merged drop approaches equilibrium. These interface shapes are visualized using a high-speed camera and followed by an examination of the timescales, axisymmetry, bridge formation, dynamic contact angle variation, energy budget, and shear rate.

Real-time monitoring of asphalt pavement structure fatigue response based on tri-axis accelerometer

ABSTRACT Fatigue damage is a notable distress of asphalt pavements. However, monitoring the development process of such distresses in real-time remained challenges for researchers. In this paper, the self-developed sensing facility has been utilized to obtain aggregate kinematic response of semi-circular specimen during the fatigue loading process in the upper-middle (H/2), lower-middle (L/2) and lower-right (L/3) positions of the specimen. Angle and acceleration variation in the X, Y, and Z directions were analysed independently at three positions. The correlation between the kinematic characteristic of the aggregate and the vertical deformation of the asphalt mixture specimen is established. The results illustrated that the asphalt mixture viscoelasticity attenuation during fatigue test caused the angle accumulation and acceleration response change of the specimen. The angle accumulation in the X-axis direction and acceleration variation in Y-axis direction of the aggregate at the H/2 position exhibited a significant three-stage change. Angle-Accumulation Rate (AAR) of change is suggested as a long-term monitoring index for the fatigue development of the asphalt mixture. The proposal of AAR index creatively combines the long-term kinematic behaviour and mechanical behaviour of asphalt mixture, making long-term and real-time monitoring of the asphalt pavement health from the perspective of kinematics become possible.

Theoretical study of the structure and stability of silyl cations with lewis bases using DFT and NBO analysis

This study investigates the intricate interplay between electronic and steric factors in shaping Si-P bond lengths, bond angles, binding energies, charge distribution, and interaction energies in silicon-centered cation-phosphine base systems. A detailed analysis reveals that (CH₃)₃Si⁺ exhibits the shortest Si-P bond lengths (2.01–2.03 Å), attributed to minimal steric hindrance and favorable electronic overlap. In contrast, (C₂H₅)₃Si⁺ displays slightly longer bond lengths (2.03–2.05 Å), while the longest bond lengths are observed in Ar₃Si⁺ (2.08–2.10 Å), due to the combined electron-withdrawing nature and steric effects of aromatic groups. Variations in bond angles further demonstrate the influence of steric bulk and electronic effects, with (C₂H₅)₃P consistently exhibiting larger bond angles (e.g., 120°–121° for Ar₃Si⁺) compared to (CH₃)₃P. Binding energy calculations identify the most favorable interaction (-28 kcal/mol) between (CH₃)₃Si⁺ and (CH₃)₃P, driven by an optimal balance of geometry and charge distribution. Charge transfer analysis indicates that (C₂H₅)₃P donates more electron density than (CH₃)₃P, consistent with trends expected from steric and electronic considerations. Natural Bond Orbital (NBO) analysis confirms a strong negative correlation between σ-donation and interaction energy, with increased σ-donation leading to stronger interaction, which are energies that are more negative. In contrast, Ar₃Si⁺ consistently exhibits weaker interactions due to the electron-withdrawing effects of its aromatic groups. These findings underscore the critical role of steric and electronic factors in defining geometry and interaction strengths, providing valuable insights for designing tailored silicon-phosphine complexes with potential applications in catalysis and material sciences.

Stress Corrosion Cracking of Brass in Chloride Solution

In this investigation, the resistance of brass material to stress corrosion cracking (SCC) in a chloride solution was assessed through adjustments in temperature (25°C, 35°C, and 45°C) and bending angles of the brass material (1.0 wt%, 2.0 wt%, and 3.5 wt%). The chosen solution closely resembles saltwater, making it suitable for testing, especially considering the widespread use of brass materials in various industrial sectors, particularly shipping. Stress corrosion cracking tends to impact brass materials under heavy loading. The primary objective of this study is to characterize the corrosion rate of brass materials. The method involved a bending test with angle variations of 180°, 90°, and 0°. Corrosion assessment utilized the Open Circuit Potential method, Anodic Polarization Tafel, and a digital microscope for the material's microstructure properties. According to the findings, brass material exhibits the lowest corrosion rate (10 x 10-6 mmpy) at a temperature of 25°C distilled water and an angle variation of 0°. Conversely, the corrosion rate increases with variations in bending angle, temperature, and the concentration of NaCl solution, as evidenced by the corrosion rate of 28.035 x 10-5 mmpy with an angle variation of 180°, to a corrosive solution of NaCl 3.5 wt% at a temperature of 45°C.

Multi-Layer Absorber based on Plasmonic Resonances for Photovoltaic Applications at Visible Spectra

This paper introduces a broadband absorber based on a multilayered, double-cylindrical-shaped metamaterial, numerically characterized for its performance. The structure comprises four interacting layers that generate plasmonic resonances. CST microwave simulations were conducted to analyze its absorption characteristics. The results demonstrate that the proposed metamaterial absorber achieves 99% absorption at 847 nm frequency region and 98% absorption in the 500-1200 nm frequency region. Additionally, polarization dependency analysis confirms that the absorber performs as a perfect, polarization-independent absorber across the studied frequency range. It exhibits high absorption in both TE and TM modes and remains unaffected by polarization or variations in the incident angle. Numerical simulations reveal that the absorption performance is driven by a combination of Fabry–Perot resonance effects, localized surface plasmons, and propagating surface plasmons. In summary, the proposed metastructure demonstrates omnidirectional absorption, polarization independence, and wide-angle incident absorption. This design shows significant potential for applications in photodetectors, active optoelectronic devices, and sensors.

Paired nerve stimulation with selective compensation effect.

In this study we investigate the selective compensation of paired peripheral nerves in healthy humans, focusing on distinct axonal conduction velocities in different fibre types. Using paired associative stimulation (PAS) with adjustable parameters, we aimed to modulate and compensate for neuronal activity along the median nerve. Six healthy volunteers (3 male, 3 female, aged: 22-49) participated in the current study. We conducted 30 experiments with the following protocol. A pair of pulses with the following parameters were applied to each volunteer: amplitude, pulse width and inter-pulse delay was generated by the dual-core programmed microcontroller STM32H745xI/G while values were set by one-board computer Jetson Nano. The microcontroller provided a pair of pulses to the DAC that applied it to nerve stimulation sites via a stimulator. During experiments, we used the following ranges: (a) current amplitudes [0-20mA], (b) pulse width [250-500 μs] and (c) delays [50-250 μs]. As the measurement of the stimulation effectiveness, we used the finger's contraction angles. Our findings reveal a significant selective compensation (inhibitory) effect over the motor responses, demonstrated through variations in finger displacement angles. By optimizing individual parameters-pulse width, inter-pulse delay, and compensatory currents-we successfully induced motor response compensation effects. Notably, consistent compensatory effects were observed across all volunteers using a pulse width of (250 μs) and an inter-pulse delay of (50 μs). These results highlight PAS's potential for developing non-invasive neuromodulation devices. However, further research is required to evaluate its efficacy in individuals with spasticity and upper motor neuron deficits.

Phantom Cooling Effects on Rotor Blade Surface Heat Flux in a Transonic Full Scale 1 + 1/2 Stage Rotating Turbine

Abstract An experimental and numerical investigation of phantom cooling effects on cooled and uncooled rotating high pressure turbine blades in a full scale 1 + 1/2 stage turbine test is presented. Objectives set to capture, separate, and quantify the effects of upstream vane film-cooling and leakage flows on downstream rotor blade surface heat flux. Multiple series of 1 + 1/2 stage rotating high pressure turbine tests were carried out in the Air Force Research Laboratory, Turbine Research Facility, at Wright-Patterson Air Force Base, Ohio. A non-proprietary research turbine was instrumented with high frequency double-sided thin film heat flux gauges custom made at AFRL. High bandwidth, time-resolved surface heat flux is measured on multiple film-cooled and non-film-cooled HPT rotor blades downstream of both film-cooled and non-film-cooled vane sectors. Upstream wake passing and heat flux is characterized on both rotor pressure and suction side surfaces, along with quantifying rotor phantom cooling effects from non-uniform first-stage vane film cooling and leakage flows. Fast response heat flux measurements quantify how rotor phantom cooling impacts the blade pressure side greatest. Measurements show upstream vane film-cooling alone can account for 50% of the rotor blade cooling effect in some instances, and even outweigh the rotor blade film cooling effect far from the blade showerhead holes. Added unsteady aero numerical simulation demonstrates how variations in inlet total temperature and incidence angle also contribute to the circumferentially non-uniform rotor heat flux. Results from this investigation aid modeling and design efforts in optimizing film cooling performance in real high-pressure turbine flow fields. Understanding the behavior of such non-uniform circumferential rotor phantom cooling effects can be critical to optimizing the efficiency, fuel consumption, range, and durability of advanced turbomachines.

Investigation of Effects of Feed Rate and Cutting-Edge Angle Variation on Surface Roughness in External Cylindrical Turning Process of Ms58 Brass Material

The Ms58 brass material was machined dry by the lathe’s external cylindrical surface turning method. Three different feeds (0.155, 0.088, and 0.028 mm/rev), 3 different cutting-edge angles (70°, 80°, and 90°), and three-spindle speeds (480, 630, and 1250 rpm) were used in machining experiments. The depth of the cut value was taken as a 0.5 mm constant. The effects of these different parameters on surface roughness values were investigated. For each surface roughness value measured from parts machined with other parameters, measurements were made five times, the largest and smallest values were discarded, and the average of the remaining 3 values was taken. This rigorous process of data collection ensured the reliability of the results. Graphs were prepared and examined with working parameters and surface roughness values. As a result, it was determined that the surface roughness value decreased with the decrease in feed and the increase in another parameter, the “cutting-edge angle” of the tool. When external cylindrical surface turning was performed with the experimental parameters of 480 rpm, a large cutting-edge angle of 90°, and a depth of cut of 0.5 mm within this study plan, the lowest average surface roughness was obtained as 1.228 µm.

The Effects of Plyometric Training on the Performance of Three Types of Jumps and Jump Shots in College-Level Male Basketball Athletes

Recent studies have shown that lower-limb plyometric training can effectively enhance muscle strength and explosiveness, which are particularly important for improving jumping ability. The purpose of this study was to evaluate the effects of plyometric training on vertical, lateral, and horizontal jumping abilities, and their subsequent impact on basketball shooting performance and sports injury prevention. A quasi-experimental design was used, recruiting 30 male college-level basketball players from Taiwan, who were randomly assigned to an experimental group (n = 15) and a control group (n = 15). Both groups participated in 2 h of basketball training daily, while the experimental group additionally engaged in plyometric training twice a week. The results revealed significant improvements in the experimental group in several key areas, including rate of force development (RFD), ground reaction force (GRF), jump height, jump distance, and both horizontal and vertical forces, across vertical, lateral, and horizontal jumps. Specifically, vertical jumps required the highest ground reaction force, followed by lateral jumps, with horizontal (step-back) jumps requiring the least. The optimal angles for the resultant force during take-off were found to be between 66.1° and 66.8° for lateral jumps, and between 56.2° and 57.2° for step-back jumps, while vertical jumps did not show significant variation in take-off angle. In terms of basketball performance, the experimental group demonstrated significantly better post-test results in all three types of jump shots, with the highest accuracy observed in the vertical jump shot, followed by the lateral jump shot, and the lowest in the step-back jump shot. Furthermore, the experimental group experienced a substantial reduction in sports injury rates, with the injury rate decreasing to 6%. These findings indicate that plyometric training not only enhances jumping performance, but also contributes to injury prevention by strengthening lower-limb muscles. This study provides a theoretical basis for coaches to develop comprehensive training programs that improve athletic performance and reduce injury risk.

Optimum part filling via layer-wise variation of raster angle in fused filament fabrication

Optimum part filling via layer-wise variation of raster angle in fused filament fabrication

Microstructural properties of Pacific yew as determined with SilviScan

Summary Pacific yew (Taxus brevifolia Nutt.) is a conifer from the northwestern United States with unusually dense and flexible wood. Because the wood of Pacific yew is not used at scale in the commercial industry, there has been no study of radial variation in wood properties or of the microstructural characteristics responsible for its atypical combination of high density and relatively low stiffness. Increment cores (12.5 mm in diameter) were obtained from 15 Pacific yew trees; SilviScan was used to observe patterns of radial variation in density, microfibril angle (MFA), and stiffness in the cores, and these patterns were compared to other conifer species. Observations included unusually dense wood with uncharacteristically low stiffness, a very slow decrease in density from pith to bark unlike any of the typical patterns of radial density variation reported for other conifers in North America, and an MFA that remained constant at its high initial value of approximately 35 degrees throughout the tree’s lifespan. Microstructural properties and macro characteristics were used to explore the ecological niche into which T. brevifolia fits, as it possesses features not shared by any other species of North American conifer.

Macro–Micro Failure Characteristics of Soft–Hard Composite Rock with Unparallel Joints: Analysis Based on DIC and AE Technique

Jointed composite rock masses are ubiquitous, where the interplay between fractures and bedding planes significantly complicates their failure mechanisms. This study conducted uniaxial compression tests on a composite rock material featuring soft and hard components with unparallel double joints. Leveraging the digital image correlation (DIC) method and acoustic emission (AE) technology, the investigation analyzed the influence of joint angles on the mechanical properties, failure modes, and crack propagation behaviors. The results indicate that the peak strength exhibits an ascending–descending–ascending trend with the variation of upper joint angle, peaking at 90°. The failure modes can be systematically categorized into three types. The failure of the specimen is predominantly influenced by the upper joint. However, when the lower joint angle is relatively flat, it becomes more prone to contributing to the failure of the specimen. The lower joint-dominated failure mode only occurs when the upper joint angle is 90°. As the lower joint angle remains at 90°, an augmentation in the upper joint angle initially leads to a decrease and subsequently to an increase in the proportion of shear cracks. In contrast, when the lower joint angle deviates from 90°, the increase of the upper joint angle initially boosts and then diminishes the proportion of shear cracks.