Zigzag Pattern Research Articles

The Impact of Stress Distribution on The Electrical Performance of Different Silver Stretchable Conductive Ink Pattern Using FEA Simulation

Stretchable conductive ink has been widely investigated to be used in the fabrication of stretchable electrical devices. Experimentation methods to test the mechanical and electrical behaviours of the stretchable conductive ink composite are commonly applied; however, not much of the computational approach has been scrutinized to validate the results further. This paper employs the finite element analysis method to investigate the relationship between the stress and strain distribution of the stretchable conductive ink with the highest strain obtained. This research validates the past experimentation works of different patterns of stretchable conductive ink for its stretchability and electrical performance. The maximum Von Mises stress (VMS) and maximum principal strain of the stretchable conductive ink played a significant role in determining its electrical performance, rather than the localisation of high stress and strain at specific locations within the stretchable conductive ink pattern. Zigzag pattern exhibited the lowest maximum stress and strain concentration at 57.826 MPa and 4.05% while straight pattern suffered the highest respective values at 118.143 MPa and 10.39%. The lower maximum Von-Mises stress and principal strain contributed to a better stretchability which is indicated by a higher strain rate prior to electrical conductivity.

Innovative enhancements in solar still performance: A comprehensive study on wick-absorber configurations

This study introduces a new thermo-fluid analysis of using wick-absorbers to enhance solar still performance. Three configurations of wick absorbers were tested in a conventional single-slope solar still: (i) Case I: individual wick balls, (ii) Case II: zig-zag wick pattern, and (iii) Case III: rectangular wick array (grid-like pattern). The study evaluates multiple parameters, including saline water temperature, daily water productivity, Nusselt number, Sherwood number, thermal and exergy efficiencies, water cost, and payback period. The addition of an absorbing plate with an insulation layer led to lower saline water temperatures and shifted peak values. Compared to a traditional still, wick utilization enhanced water productivity by 45.8 %, 84.5 %, and 86 % for Cases I, II, and III, respectively, due to increased evaporation rates. This resulted in a relative enhancement in daily thermal efficiency by 64 %, 76 %, and 97.5 %, respectively. Additionally, four correlations were developed to describe Nusselt and Sherwood numbers, with a maximum deviation of 25 %. Economic analysis demonstrated cost-effectiveness, significantly reducing water cost and the payback period by 37 %, 39 %, and 44 % for Cases I, II, and III, respectively, compared to the conventional system.

Highly isolated electrically compact UWB MIMO antenna for wireless communications applications

A multiple-input multiple-output Ultra-Wide Band (UWB) antenna with a compact size of 0.8λ x 0.7λ is proposed. The presented structure is constituted with patch geometry on a planar surface. The radiator consists of three counter U-shaped conducting strips united with a patch structure where two are positioned nearby and the third geometry covers the remaining conducting strips. A corrugated design has been created on a ground plane in which zigzag pattern slots are engineered to receive high isolation of more than 20 dB. The configured antenna radiates over a wide frequency spectrum of 3.10 GHz–11.85 GHz. It offers a fractional bandwidth of 195 % with a gain of 2.80 dBi, 3.08 dBi, and 2.72 dBi for targeted resonances. The antenna radiation patterns and MIMO diversity parameters are also presented. The acceptable values of ECC (<0.05 abs), MEG (−6 dB to −8 dB), CCL (<0.02 bits/sec/Hz) were found. The fabricated model was tested inside an anechoic chamber environment to receive the measured response with optimum accuracy through multiple iterations. The measured response shows a strong correlation with numerically computed responses finding the presented antenna suitable for WiMAX, WLAN (max protocol) and radar applications.

Models of traditional games in physical education and sports: its effect on increasing the motor devel-opment of elementary school students

Each country has its own traditional games. Traditional games need to be continued so that they do not become extinct, besides that traditional games provide benefits for the motor development of elementary school students. The research aims to determine traditional game models in physical education and sports: its effect on increasing the motor development of elementary school students. This research is an SLR type using the PRISMA method. It focuses on traditional games and their impact on motor development among elementary school students. The inclusion criteria encompass journal articles published between 2020 and 2024. The article retrieval process utilizes the Publish or Perish 8 application and accesses databases such as Google Scholar, Pubmed, ScienceDirect, and ProQuest. Based on the results of this research, the game models in Physical Education and Sports on motor development in elementary school students in the world over the last 5 years include Pittu Garam, fortification, Gobak Sodor, Engklek, Grave Jump, Cat and Mouse, Zig-Zag Pattern Sack Racing, Cat Squatting, Sintren Plate Breaker, fortified, like a snake, sack race, and shell stilts running race. The conclusion of this research is that based on the review article, it shows that all types of traditional game models can improve the motor development of elementary school students. A traditional game model that can improve students' fine and gross motor skills is Engklek. Keywords: Traditional Game Models, Physical Education and Sports, Motor Development, Elementary School Students

International expert consensus statement on physiological interpretation of cardiotocograph (CTG): First revision (2024)

The first international consensus guideline on physiological interpretation of cardiotocograph (CTG) produced by 44 CTG experts from 14 countries was published in 2018. This guideline ensured a paradigm shift from classifying CTG by arbitrarily grouping certain features of the fetal heart rate into different “categories”, and then, randomly combining them to arrive at an overall classification of CTG traces into “Normal, Suspicious and Pathological” (or Category I, II and III) to a classification which is based on the understanding of fetal pathophysiology. The guideline recommended the recognition of different types of fetal hypoxia, and the determination of features of fetal compensatory responses as well as decompensation to ongoing hypoxic stress on the CTG trace. Since its first publication in 2018, there have been several scientific publications relating physiological interpretation of CTG, especially relating to features indicative of autonomic instability due to hypoxic stress (i.e., the ZigZag pattern), and of fetal inflammation. Moreover, emerging evidence has suggested improvement in maternal and perinatal outcomes in maternity units which had implemented physiological interpretation of CTG. Therefore, the guideline on Physiological Interpretation of CTG has been revised to incorporate new scientific evidence, and the interpretation table has been expanded to include features of chorioamnionitis and relative utero-placental insufficiency of labour (RUPI-L).

Survival strategies of Bar-tailed Godwit in tropical sand beaches: Straight-line and zigzag foraging techniques

The near-threatened Bar-tailed Godwit (Limosa lapponica) makes the longest non-stop endurance flights among shorebirds. They are regular winter visitors to the Kadalundi-Vallikkunnu Community Reserve and adjoining sand beaches along the west coast of India. The research investigates their foraging strategies within sand beaches, observed over six years (2016-2022). Extensive field observations across major sand beaches documented two distinct modes of continuous stitching behaviour; a straight-line mode and a zigzag mode. Despite predation pressure and human disturbances, Bar-tailed Godwits achieved high prey capture rates, likely due to the abundance of benthic invertebrates. The study also revealed the prevalence of this behaviour and its association with rate of prey consumption, particularly focusing on the availability of Cosmonotus crabs, the dominant prey species. The zigzag pattern, was associated with higher prey capture rates, suggesting an adaptive response to prey distribution. Our findings suggest that, this unique foraging strategy allows Bar-tailed Godwits to optimize prey capture while conserving time and energy, especially in resource-scarce environments. Furthermore, the implications of these behaviours are discussed in the context of prey availability, nutrient content, and the energetic demands of long-distance migration, shedding light on to the adaptive mechanisms employed by shorebirds in challenging habitats.

Evaluation of Auditorium Acoustics in the Faculty of Mathematics and Science Education, Universitas Pendidikan Indonesia, Bandung.

Abstract As a space whose function is prioritized for speeches, the auditorium must respond well to acoustics so that listeners get audibly comfortable when listening to speakers speak. In this study, the Japan International Cooperation Agency (JICA) Auditorium located in the Faculty of Mathematics and Natural Sciences will be simulated to determine the acoustic quality of the auditorium. The method used is simulation using Ecotect software. The simulation is done by creating a 3D model and inputting several parameters, such as the absorption coefficient of the material used in the auditorium and the placement of speakers in it. This simulation determines the reverberation time, the initial decay time, or how long the room muffles the sound after the sound source stops, and the sound distribution produced by the sound source or speaker in the room. Based on the simulation results, the acoustic quality of the JICA auditorium is good. This is due to several factors, such as the selection of materials with a high absorption coefficient on the back wall and the shape of the room design, which uses geometric shapes with zigzag patterns on the ceiling and walls, as well as the slope used on the floor and ceiling.

Comprehensive numerical and experimental analysis the impact of employing vortex generators on evaporative cooling process

Reduced energy usage is an important concern in vapor compression cooling systems, particularly in hot climates. These systems function poorly in hot weather and consume a lot of electricity. Evaporative condensers use the cooling impact of evaporation to facilitate the process of heat rejection and thereby increase energy efficiency. This work evaluates the impact of employing vortex generators on the performance of an evaporative condenser. The analysis is performed using a validated numerical model, a commercial CFD code. The proposed vortex generators are parallel plates with sinusoidal and zigzag patterns. Dry air enters a channel equipped with four vortex-generating plates and water spray. The incoming dry air cools due to the two-phase heat transfer during air contact with the sprayed water droplets, and the cooled air with the proper humidity level exits the channel. The investigated parameters include longitudinal nozzle position, inlet air flow rate, pitch, and the height of the vortex generator plates in two sinusoidal and zigzag modes and the obtained results are compared with the plain channel model. Greater inlet air velocity resulted in superior output temperatures and pressure drops, yet lower outlet relative humidity and water mass percentage. According to the findings, the air pressure drop and outlet dry temperature are raised by 152 % and 5 %, respectively, when the incoming air velocity is altered from 0.4 to 0.6 m. s−1 (50 % growth), and the nozzle position is moved from X = 1.35 m to X = 1.85 m (37.04 % change) from the channel entrance, while the relative humidity and water mass fraction are decreased by 19 % and 11 %, respectively. Additional research revealed that the vortex flow level is lower when the nozzle is positioned farther away from the plates, and the water spray's impact on lowering the local air temperature in vortex-flowing areas is more substantial when it is positioned closer to the plates. Furthermore, increasing wave height and pitch values of vortex generators result in a more extensive air pressure drop in the channel, and vice versa. This means that, at a fixed pitch, a higher plate wave height raises the amount of vortex flows. According to the findings, sinusoidal vortex plates have better efficiency than the zigzag ones, and in a channel equipped with water spray, the use of vortex plates before the water spray nozzles lowers the dry temperature at the outlet by about one °C compared to that of the plain channel.

Mechanical and failure behaviors of adhesively bonded dissimilar materials joints incorporating bio-inspired morphological irregularities

Adhesive dissimilar material joints between stainless steel grade 316L and polyethylene terephthalate glycol (PETG) plastic were examined, in which irregular interface morphologies inspired by natural sutures were incorporated. The joint interfaces exhibited various teeth-like, non-repetitive zigzag patterns based on a pseudo-randomization method and sutural interdigitation index. Effects of their irregularities on mechanical and failure characteristics of adhesive butt joints were studied by means of experiments and FE simulations. The cohesive zone model, Drucker-Prager plasticity model and ductile failure criterion were applied for the interface and PETG, respectively. Predicted load-displacement curves of joints with different teeth profiles were well validated. The degree of irregularity became higher to 20%, 40%, and 60%, the joint strengths decreased by 1.47%, 5.39%, and 11.95%, while the total energies to failure increased by 110.74%, 129.33%, and 161.23%, accordingly. More inhomogeneous morphologies led to earlier local damage initiation, but enhanced damage evolution range by impeding abrupt joint separation. Smaller teeth angles provided higher joint strength, whereas significant declines of bonding strength were observed by too acute teeth angle due to excessive stress localization and resulting teeth breakage. The teeth angle of 45º enabled the superior joint performance owing to a proper combination of interlocking and large adhesive force under shear stress state. Finally, a key insight for designing an optimal dissimilar joint with morphological irregularities was provided.

Exploring the atomic-scale dynamics of Fe3O4(001) at catalytically relevant temperatures using FastSTM

Surfaces and interfaces of functional nanoscale materials are typically highly dynamic when employed at elevated temperatures. Both, lateral surface and vertical bulk exchange diffusion processes set in, which can be relevant for applications such as heterogeneous catalysis. Time-resolved scanning tunneling microscopy (STM) is being pushed to ever faster measurement modes to follow such dynamic phenomena in situ. Here, we present FastSTM movies monitoring a range of atomic-scale dynamics of a prototypical reducible oxide catalyst support, Fe3O4(001), at elevated temperatures. Antiphase domain boundaries between two domains of the reconstructed surface exhibit local mobility from around 350 K, while Fe-rich point defects, in a stable equilibrium with the bulk, appear to diffuse in a peculiar zigzag pattern above 500 K. Finally, exploiting the diffusivity of Fe interstitials, we follow the propagation of step edges in the topmost atomic layer of the Fe3O4(001) surface in an oxygen atmosphere.

The role of altruistic behavior in emergency evacuation: A simulation study

Given the rising threat of terror attacks and the increasing frequency of natural disasters attributed to climate change, enhancing evacuation capacities in various spaces has become crucial for saving lives and accelerating recovery processes. This study investigates the influence of altruistic behavior on evacuation efficiency by developing a social force model that categorizes individuals into three demographic groups: youth, middle-aged, and seniors. Simulation experiments based on the model were conducted to evaluate the impact of altruistic behavior on evacuation efficiency under different conditions, such as evacuation capacity, reliability, and recovery time. The simulation results show that a higher probability of falling leads to longer evacuation times. While an increase in the probability of altruistic behavior improves evacuation efficiency, excessive altruistic behavior causes evacuation times to vary in a zigzag pattern. When the help range exceeds 0.7m, evacuation efficiency fluctuates without a clear trend of improvement.

Measurement of the Tension Loss in a Cable Traveling Over a Pulley, for Low-Speed Applications

BackgroundWire ropes or cables are widely used solutions for force transmission in several industrial applications. Their hysteretic behavior may significantly influence control accuracy or the force transmission’s efficiency. Cables traveling through sheaves can suffer a relatively high tension loss, which this article addresses.ObjectiveThis paper aims to present a simple measurement method for the tension loss in cables traveling over sheaves on bearings.MethodsThe presented measurement method uses a cable-pulley system with a spring installed at one cable end. The pulley is moved in a zig-zag pattern. The force is measured on both cable ends; this way, the tension loss can be determined as a function of the cable tension. The force was measured with S-type load cells, which are highly sensitive to off-axis loads; this problem can be overcome by proving that the force measurement has a proportional error, which can be eliminated from the frictional coefficient. The measurements are compared to two models from the literature; one approximates the power loss of a cable drive by calculating the work of the cable’s inner friction, and the other is a cable bending model, which is used to determine the hysteretic energy of the cyclic bending.ResultsThe result of the measurement evaluation is a coefficient of tension loss that contains the loss coming from the cable bending and the bearing friction. Four cable types and a steel strip with negligible bending hysteresis were measured, the latter for control measurement. It is demonstrated that a significant part of the tension loss originates from the inner friction of the cable and that it is equal to the hysteretic energy of the cyclic bending.ConclusionThe presented method provides a robust measurement for the tension loss factor in cables traveling over pulleys. It is proven that the off-axis loads cause a proportional error in the force measured by S-type load cells, and this measurement error can be eliminated from the tension loss factor. The results demonstrated that the presented models can be used to predict the tension loss in cables traveling over sheaves.

Soil Chemical and Physical Properties in Taungya and Non-Taungya Plots at Sao Hill Forest Plantation, Tanzania

This study compared soil physical and chemical properties in Tungya and Non-Taungya plots at Sao Hill Forest plantation, Tanzania. Soil samples were collected from 0-20cm depth in February and May Using a zigzag pattern to ensure representative coverage. Physical properties (bulk density, porosity, Soil moisture content, soil texture) and chemical properties (soil pH electrical conductivity, total nitrogen and available phosphorous) were analyzed using standard laboratory methods. Results showed significant differences between the two management practices. In February Non-Taungya plots had higher bulk density(1.33±0.151/cm3) compared to Taungya plots (1.16±0.107 g/cm3; p&lt;0.001), while Taungya plots showed higher porosity (56.12%±4.06p&lt;0.001). May sampling also revealed differences with non-Taungya plots maintaining higher bulk density (1.32±0.15 g/cm3) compared to Taungya plots (1.08±0.09 g/cm3); p&lt;0.001). Soil texture analysis showed no significant differences in sand content between treatments. However, silt content was significantly higher in Taungya plots (13.27 ± 3.849%) compared to non-Taungya plots (10.69 ± 3.23%; p=0.007), while clay percentage did not differ significantly. Soil chemical properties, non-Taungya plots had higher pH (4.67±0.47) compared to Taungya plots (4.3±0.22; p&lt;0.001) while electrical conductivity (0.04±0.04 dS/m) compared to Taungya plots (0.01±0.01 dS/m; p&lt;0.001). Taungya plots showed higher total nitrogen (0.04±0.01%; p&lt;0.0031) compared to non-Taungya plots (0.035±0.01%). In additional May available phosphorous in Taungya plots was (3.95±0.55 mg/kg; p&lt;0.001) compared to non-Taungya plots (1.97±0.32 mg/kg). These results suggest that Taungya practices significantly influence soil properties, potentially impacting soil quality and forest productivity. The study provides valuable awareness for sustainable forest management and highlights the need for long-term monitoring of soil properties under different management systems in plantation forests

Quantitative classification evaluation model for tight sandstone reservoirs based on machine learning

Tight sandstone reservoirs are a primary focus of research on the geological exploration of petroleum. However, many reservoir classification criteria are of limited applicability due to the inherent strong heterogeneity and complex micropore structure of tight sandstone reservoirs. This investigation focused on the Chang 8 tight reservoir situated in the Jiyuan region of the Ordos Basin. High-pressure mercury intrusion experiments, casting thin sections, and scanning electron microscopy experiments were conducted. Image recognition technology was used to extract the pore shape parameters of each sample. Based on the above, through grey relational analysis (GRA), analytic hierarchy process (AHP), entropy weight method (EWM) and comprehensive weight method, the relationship index Q1 between initial productivity and high pressure mercury injection parameters and the relationship index Q2 between initial productivity and pore shape parameters are obtained by fitting. Then a dual-coupled comprehensive quantitative classification prediction model for tight sandstone reservoirs was developed based on pore structure and shape parameters. A quantitative classification study was conducted on the target reservoir, analyzing the correlation between reservoir quality and pore structure and shape parameters, leading to the proposal of favourable exploration areas. The research results showed that when Q1 ≥ 0.5 and Q2 ≥ 0.5, the reservoir was classified as type I. When Q1 > 0.7 and Q2 > 0.57, it was classified as type I1, indicating a high-yield reservoir. When 0.32 < Q1 < 0.47 and 0.44 < Q2 < 0.56, was classified as type II. When 0.1 < Q1 < 0.32 and 0.3 < Q2 < 0.44, it was classified as type III. Type I reservoirs exhibit a zigzag pattern in the northwest part of the study area. Thus, the northwest should be prioritized in actual exploration and development. Additionally, the initial productivity of tight sandstone reservoirs showed a positive correlation with the porosity, permeability, sorting coefficient, coefficient of variation, and median radius. Conversely, it demonstrated a negative correlation with the median pressure and displacement pressure. The perimeters of pores, their circularity, and the length of the major axis showed a positive correlation with the porosity, permeability, sorting coefficient, coefficient of variation, and median radius. On the other hand, they exhibited a negative correlation with the median pressure and displacement pressure. This study quantitatively constructed a new classification and evaluation system for tight sandstone reservoirs from the perspective of microscopic pore structure, achieving an overall model accuracy of 93.3%. This model effectively predicts and evaluates tight sandstone reservoirs. It provides new guidance for identifying favorable areas in the study region and other tight sandstone reservoirs.

Possible mechanism of action potential propagation mediated by static electric field: A novel assumption of understanding nerve interaction and ephaptic coupling

The generation and propagation of physical signals in living biosystems are continuous issues. Traditional Hodgkin-Huxley model based on ionic current conduction could not explain the fast transmission of action potential in myelinated axons and factors influencing action potential velocity. We propose that the ion flow induced by Nav channel generates near field quasi-static electric field at extracellular space, termed as an ephaptic field which is able to excite nearby passive axons. Our simulation indicates that the static electric field produced by sodium ion channels in one node of Ranvier is improbable to stimulate the ion channels in the adjacent neighboring node. However, the ion channel ring in one node of Ranvier could induce the shift of membrane potential (0.01 mV) on the node at nearby axons (100 μm) in a bundle of axon synchronously, suggesting zig-zag propagation of action potential. Together with the superposition effect of ephaptic feedback field generated by the synchronized movement of adjacent parallel axons stimulate the adjacent node of the original axon, strengthen the action potential to travel in a zig-zag pattern. Our model also provides an explanation for the rapid velocity of action potential propagation reported in experimental studies.

Influence of pH value on erosive wear of 3D-printed polylactic acid for multiphase flow

Abstract Slurry erosion presents a critical challenge in hydrocarbon and cement processing industries, as well as in abrasive water jet cutting systems, leading to diminished operational efficiency and elevated maintenance costs. This study investigates the erosive wear behavior of Poly-Lactic Acid (PLA) fabricated with varying infill microtextures—zigzag, concentric, and grid—under diverse pH conditions (2.73, 7.75, and 10.15) using garnet particles as the erodent. The results demonstrate that optimal operational conditions for PLA are achieved with a grid microtexture, a pH of 7.75, and a 325 μm erodent size. Conversely, the most severe wear occurs under a pH of 10.15, a 600 μm erodent size, and a zigzag microtexture. The grid microtexture is the most effective in minimizing erosion, while the zigzag pattern shows a 16.68% increase in wear when compared to the grid microtexture. Additionally, a shift from a slightly basic to a highly acidic environment increases wear by 1%, whereas a transition to a highly basic environment leads to a 32.6% increase in erosion within the grid microtexture. The study highlights the significant contributions of infill microtexture (64%), erodent size (23.7%), and pH value (11%) to the overall erosion rate.

Influence of scanning pattern on accuracy, time, and number of photograms of complete-arch implant scans: A clinical study

ObjectivesTo measure the influence of scanning pattern on the accuracy, time, and number of photograms of complete-arch intraoral implant scans. MethodsA maxillary edentulous patient with 7 implants was selected. The reference implant cast was obtained using conventional methods (7Series Scanner). Four groups were created based on the scanning pattern used to acquire the complete-arch implant scans by using an intraoral scanner (IOS) (Trios4): manufacturer's recommended (Occlusal-Buccal-Lingual (OBL)), zig-zag (Zig-zag), circumferential (Circumf), and novel pattern that included locking an initial occlusal scan (O-Lock group) (n = 15). Scanning time and number of photograms were recorded. The linear and angular measurements were used to assess scanning accuracy. One-way ANOVA and Tukey tests were used to analyze trueness, scanning time, and number of photograms. The Levene test was selected to assess precision (α=0.05). ResultsStatistically significant differences in trueness were detected among OBL, Zig-zag, Circumf, and O-Lock regarding linear discrepancy (P<0.01), angular discrepancy (P<0.01), scanning time (P<0.01), and number of photograms (P<0.01). The O-Lock (63 ± 20 µm) showed the best linear trueness with statistically significant differences (P < 0.01) with Circumferential (86 ± 16 µm) and OBL (87 ± 19 µm) groups. The O-Lock (93.5 ± 13.4 s, 1080 ± 104 photograms) and Circumf groups (102.9 ± 15.1 s, 1112 ± 179 photograms) obtained lower scanning times (P < 0.01) and number of photograms (P < 0.01) than OBL (130.3 ± 19.4 s, 1293 ± 161 photograms) and Zig-zag (125.7 ± 22.1 s, 1316 ± 160 photograms) groups. ConclusionsThe scanning patterns tested influenced scanning accuracy, time, and number of photograms of the complete-arch scans obtained by using the IOS tested. The zig-zag and O-Lock scanning patterns are recommended to obtain complete-arch implant scans when using the selected IOS.

Road resuspension PM2.5 from two vehicles driving in parallel by CFD method: The characteristics and population exposure

Particulate matter (PM) from the road resuspension dust of vehicles driving can deteriorate urban air quality. The goal of our study was to develop a discrete phase model and sliding grid technology to simulate the distribution characteristics of resuspension PM2.5 from vehicle road dust, and to analyze PM2.5 exposure of drivers and pedestrians caused by resuspension dust. The results indicated that the maximum height of PM2.5 concentration at the XZ section at 1–10 s varied in a zigzag pattern, with the lowest at 3.37 m at 1 s and the highest at 5.85 m at 2 s. PM2.5 concentration diffusion presented a "two lungs within one bracket" shape at Z = −0.03 m section and PM2.5 was gradually diffused from the tire to the two sides of the vehicle at 1–10 s. PM2.5 concentration at y = 5.5 m line of X = −15 m section gradually decreased with ground height increasing. The average PM2.5 concentration at Z = 1.25 m section at 1–10 s was 1.86, 3.17, 6.85, 8.85, 12.78, 14.69, 16.64, 18.96, 21.50, and 22.98 μg/m3, respectively. The average PM2.5 concentration was directly proportional to the change in road dust mass flow rate. The range of PM2.5 concentration of points a (left driver), b (right driver), c1 (pedestrian standing still for 3 m on right side of right vehicle) and c2 (pedestrian walking at a speed of 1.5 m/s) were 0–49.8, 0–183.0, 0–16.5, and 0–59.8 μg/m3, and the time of the maximum PM2.5 concentration for a, b, c1, and c2 was 5, 6.5, 4.5 and 5 s, respectively. These results indicated that the driver of point b had the highest exposure concentration within 1–10 s, which was 5.8 times that of the driver of point a, 7.7, and 2.9 times that of pedestrians of points c1 and c2. These results can provide basic data for road dust emissions and population exposure risk management.

A comparative study on mechanical properties between linear and zigzag pattern holes reinforced with tialite particles during FSW of AA6082 alloy

In this study, a comparison between linear and zigzag patterned holes is carried out where the holes in the pattern are incorporated with tialite/aluminium titanate (Al2TiO5) particles at the weldment region during friction stir welding of AA6082-T6 aluminium alloy. Different values of tool rotational speed (TRS: 1000, 1200 and 1400 rpm) and welding speed (WS: 35, 40 and 45 mm/min) are considered for the fabrication of joints by both patterns. Visually, no defects are found in all the welded samples. Microstructural analysis has proven that the uniform distribution of particles along the weld region can be obtained by using a zigzag pattern. Maximum hardness is found in the stir zone (SZ), whereas minimum hardness is found in the heat-affected zone (HAZ) for all the samples. The maximum ultimate tensile strength (UTS: 268 MPa), maximum yield strength (YS: 200 MPa) and relatively higher elongation (EL: 7.89%) are exhibited by the Z5 sample, whereas minimum UTS (206 MPa) and minimum YS (142 MPa) was exhibited by L3 and Z7 samples, respectively.

Trueness of Intraoral Scanners in Different Scan Patterns for Full-Arch Digital Implant Impressions.

The optimal scan pattern for full-arch digital implant impressions remains to be determined. This study aimed to analyze the effects of different scan patterns on the trueness of intraoral scanners for full-arch digital implant impressions. A maxillary plaster model with 4 implant analogs was employed as the master model. Scan bodies were attached to the master model and scanned with a laboratory scanner to obtain reference data. Test scans were obtained using 3 different scan patterns with Cerec Primescan and Trios 3. Each test datum was superimposed onto the reference data. The trueness was assessed by determining the 3D distance and angular deviations between the test and reference data. Significant differences in 3D distance deviation were detected among the scan patterns for both scanners. Significant differences in angle deviation were detected among the scan patterns for the Cerec Primescan, whereas it was not substantial for the Trios 3. Cerec Primescan exhibited superior trueness across all scan patterns compared with Trios 3. The zigzag pattern resulted in more accurate scans for the Cerec Primescan, whereas both the zigzag and occlusal-palatal-buccal patterns showed higher accuracy for the Trios 3.