Variable Thickness Research Articles

Thickness monitoring of threshing mixture on the oscillating plate of corn grain harvester

Cleaning is a critical operation in the corn grain harvesting process, and the operation is seriously affected by the uneven distribution of the threshing mixture on the oscillating plate. To monitor the thickness of the threshing mixture on the oscillating plate of the corn grain harvester, in this study, we adopted the lever principle to design a corn threshing mixture thickness monitoring device based on the piezoresistive effect and theoretically analyzed the lever impact mechanics. The factors affecting the force on the sensor of the monitoring device are the vibration frequency of the oscillating plate, the thickness of the threshing mixture, and grain moisture content, which were obtained through theoretical analysis. The operational performance of the corn threshing mixture thickness monitoring device was assessed through a set of single-factor experiments, revealing the influence laws of three factors on the impact voltage: vibration frequency, thickness of the threshing mixture, and grain moisture content. A back-propagation (BP)11Back-propagation (BP) neural network prediction model was established using an orthogonal experiment with impact voltage, vibration frequency, and grain moisture content as input layers and the thickness of the corn threshing mixture as the output layer. An STM32 microcontroller was used as the primary control unit to build a thickness monitoring data acquisition and processing system that could process and operate the impact voltage collected by the pressure sensor and the vibration frequency signal collected by a Hall sensor. The data were wirelessly transmitted to a PC to predict the thickness of the threshing mixture by using the trained BP neural network. The experimental results of monitoring the variation in corn threshing mixture thickness demonstrated that the device could effectively monitor changes in thickness. The monitoring accuracy of the monitoring device was found to be over 90%, and the system can be used for monitoring the threshing mixture thickness on the oscillating plate of the corn grain harvester.

Two-dimensional ASEP model to study density profiles in CVD growth

The growth of two-dimensional (2D) transition metal dichalcogenides using chemical vapor deposition has been an area of intense study, primarily due to the scalability requirements for potential device applications. One of the major challenges of such growths is the large-scale thickness variation of the grown film. To investigate the role of different growth parameters computationally, we use a 2D asymmetric simple-exclusion process (ASEP) model with open boundaries as an approximation to the dynamics of deposition on the coarse-grained lattice. The variations in concentration of particles (growth profiles) at the lattice sites in the grown film are studied as functions of parameters like injection and ejection rate of particles from the lattice, time of observation, and the right bias difference between the hopping probabilities towards right and towards left) imposed by the carrier gas. In addition, the deposition rates at a given coarse-grained site is assumed to depend on the occupancy of that site. The effect of the maximum deposition rate, i.e., the deposition rate at a completely unoccupied site on the substrate, has been explored. The growth profiles stretch horizontally when either the evolution time or the right bias is increased. An increased deposition rate leads to a step-like profile, with the higher density region close to the left edge. In 3D, the growth profiles become more uniform with the increase in the height of the precursor with respect to the substrate surface. These results qualitatively agree with the experimental observations.

Air leakage mechanism and hole sealing technology in directional long-drilled perimeter rock-borehole composite fissures: for gas enrichment in varying coal-seam thickness change areas

The issue of gas enrichment in the tectonic zone of coal seams, which poses significant threats to coal mine safety and leads to gas disasters, is primarily addressed through borehole extraction. The quality of this extraction is notably influenced by air leakage and sealing technologies used during drilling. To tackle the problem of gas leakage in directional long boreholes within the floor, a composite fissure leakage model for the surrounding rock and borehole is developed. This model inverts the characteristics of coal seam thickness variations and abnormal gas enrichment through heterogeneous geostatistical modeling. It enables the quantitative characterization of the air leakage mechanism in directional long boreholes of the bottom plate and proposes an effective sealing process. Due to damage and disturbance, fissures and irregular plastic zones form around the excavated roadway, which are major contributors to air leakage. Over time, the air content in the coal and rock seams gradually increases while the gas content and concentration decrease continuously. Compared to the polyurethane "two plugs and one injection" sealing process, the multi-stage grouting and sealing process provides a more stable gas extraction concentration and flow rate in the sealed drill holes. This process effectively seals the fissure zones of the roadway, reduces air leakage from the boreholes, and improves gas extraction concentration.

Quantifying Morphological Changes in Middle Trapezius With Ultrasonography and Histogram Matching for Participants With and Without Facioscapulohumeral Dystrophy

Objective: Echogenicity is a biomarker in facioscapulohumeral muscular dystrophy (FSHD). Currently, it is not possible to compare echogenicity values, derived using quantified muscle sonography capture, based on different equipment instrumentation settings. Image normalization, using histogram matching, could address this limitation. The aim of this study was to investigate the sensitivity of histogram matching, with trapezius muscle echogenicity values, in participants with and without FSHD. Materials and Methods: Sensitivity analysis of a single measurement timepoint case control study of participants with FSHD, using age- and gender-matched controls. Correlations between trapezius muscle echogenicity, muscle thickness, and shoulder range of movements were also completed. Results: Data were collected for 14 participants, seven with FSHD and seven controls. The cohort had a mean age of 41.6 years. The FSHD group echogenicity values (118.2) were higher than controls (42.3), respectively, as well as statistically significant ( p = .002). An overall variance of 6.2 (range = −2.9 to 15.4) was identified between the reference images. Echogenicity explained 81% of the variance in muscle thickness and 74% of the variance in range of movement muscle thickness was explained by 61% of the variance for range of movement. Conclusion: Histogram matching for comparison of echogenicity was required. Different reference images affect echogenicity values, but the variability was less than between group differences. Further longitudinal evaluation based on a larger sample of participants is needed.

Light patterning semiconductor nanoparticles by modulating surface charges.

Optical patterning of colloidal particles is a scalable and cost-effective approach for creating multiscale functional structures. Existing methods often use high-intensity light sources and customized optical setups, making them less feasible for large-scale microfabrication processes. Here, we report an optical patterning method for semiconductor nanoparticles by light-triggered modulation of their surface charge. Rather than using light as the primary energy source, this method utilizes UV-induced cleavage of surface ligands to modify surface charges, thereby facilitating the self-assembly of nanoparticles on a charged substrate via electrostatic interactions. By using citrate-treated ZnO nanoparticles, uniform ZnO patterns with variable thicknesses can be achieved. These multilayered ZnO patterns are fabricated into a UV detector with an on/off ratio exceeding 104. Our results demonstrate a simple yet effective way to pattern semiconductor nanoparticles, facilitating the large-scale integration of functional nanomaterials into emerging flexible and robotic microdevices.

On the control of thickness in gas blow metal sheet forming processes: A review

Although the advantages of formability are notable, blow-forming processes, which are classified as sheet metal stretching processes, present limits in terms of uniformity of the thicknesses of the produced product. This is a review paper that collects the numerical and experimental studies of the literature on the new metal sheet forming techniques to improve formability and production efficiency. In particular, the focus is on (a) the multi-phase forming technique and (b) the techniques involving a blank with a profile of variable initial thickness. These techniques promote a strategic decrease of the thickness in some areas of the part to be formed to improve the final distribution of thicknesses in those most critical areas of the component to be made. The paper presents the finite element modelling works of the literature to predict the accuracy of a formed part in terms of the uniformity of its thickness that avoids breakups; thus, allowing to design and establish the feasibility of new forming techniques. The parameters influencing the forming processes were analysed by comparing the results of the finite element simulations in terms of the thickness distribution of the finished product and forming times. This paper presents also the experimental forming tests that verified these forming techniques and provided a thickness profile that reduces maximum thinning and forming times in comparison with the traditional processes. The conclusion of the paper demonstrates that these forming techniques allow to obtain a more uniform thickness of the formed part in a shorter processing time.

Comparison of vibration values of rotating discs with variable parameters obtained by finite element analysis modeling with different machine learning algorithms

PurposeRotating functionally graded (FG) disks of variable thickness generates vibration. This study aims to analyze the vibration generated by the rotating disks using a finite element program and compare the results obtained with the regression methods.Design/methodology/approachTransverse vibration values of rotating FG disks with variable thickness were modeled using different regression methods. The accuracies of the obtained models are compared. In the context of comparing regression methods, multiple linear regression (MLR), extreme learning machine (ELM), artificial neural networks (ANNs) and radial basis function (RBF) were used in this study. The error graph between the observed value and the predicted value of each regression method was obtained. The error values of the regression methods used with scientific error measures were calculated.FindingsThe analysis of the transverse vibration of rotating FG disks with the finite element program is consistent with the studies in the literature. When the variables and vibration value determined on the disk are modeled with ELM, MLR, ANN and RBF regression methods, it is concluded that the most accurate model order is RBF, ANN, MLR and ELM.Originality/valueThere are studies on the vibration value of rotating discs in the literature, but there are very few studies on modeling. This study shows that ELM, MLR, ANN and RBF, which are machine learning methods, can be used in modeling the vibration value of rotating discs.

Improvement of microwave absorbing capability on the soft magnetic/hard magnetic/perovskite composites

Abstract This paper reports an increase in the ability to absorb microwaves from a composite made of combination between soft and hard magnetic materials, perovskite material, and an epoxy as matrix of composite, Ni0.5Zn0.5Fe2O4/Ba0.6Sr0.4Fe9.5Al0.5MnTiO19/FeTiO3/epoxy (NBFE) with a wt% ratio of 5:3:2:10. Composite samples were made using the mechanical alloying method with milling techniques and sintered at a temperature of 1000 °C for 5 h. NBFE composites were studied to increase the ability to absorb microwaves at 2–18 GHz frequencies with thickness variations of 1 mm and 2 mm. The results obtained, the composite sample Ni0.5Zn0.5Fe2O4/Ba0.6Sr0.4Fe9.5Al0.5MnTiO19/FeTiO3/epoxy has the ability to absorb microwaves with the best reflection loss value −37.47 dB with a bandwidth almost reaches 11.32 GHz in the 2–18 GHz frequency range.

Quantitative Evaluation of Enamel Thickness in Maxillary Central Incisors in Different Age Groups Utilizing Cone Beam Computed Tomography a Retrospective Analysis

Background/Objectives: The presence of enamel on the tooth surface is crucial for the long-term success of minimally invasive adhesive restorations such as dental veneers. Our study aims to evaluate the enamel thickness in the incisal, middle, and cervical portions of the labial surface of the upper central incisors using cone beam computed tomography (CBCT). This imaging method provides detailed and accurate three-dimensional images with a low radiation dose, allowing an accurate assessment of enamel thickness. The analysis aims to identify variations in enamel thickness depending on the age and different levels of the labial tooth surface. Methods: 800 CBCT scans performed for diagnostic or therapeutic purposes on patients aged 18–60 years were analyzed. The data were gathered from the imaging archives of private practitioners from Targu Mures and the “George Emil Palade” University of Medicine, Pharmacy, Science, and Technology of Targu Mures. Enamel thickness measurements were conducted using the OnDemand3D Communicator CBCT evaluation program, with subsequent statistical analysis performed using GraphPad Instat Prism software. Results: Results showed significant variation in enamel thickness between the incisal, middle, and cervical segments of the labial surface of the upper central incisors. A decrease in enamel thickness with age has been observed. In patients aged 18–40, mean values of enamel thickness 1 mm and 3 mm above the cementoenamel junction (CEJ) were 0.48 ± 0.092, respectively, 0.819 ± 0.158. In patients over 40, the mean values were 0.454 ± 0.116 and 0.751 ± 0.067 at 1 mm, respectively, 3 mm above the CEJ. Statistically significant differences were found between the two age groups at 1 mm and 3 mm above the CEJ, with p < 0.0001 and p = 0.0214. Conclusions: A statistically significant decrease can be observed in enamel thickness in almost the entire labial surface of the upper central incisors with aging. The varied thickness of the enamel at different tooth levels requires individualized planning for each patient to maximize the long-term aesthetic and functional results.

Frontal Bone Morphology in Different Age and Gender Groups Using Computed Tomography.

The shape of the forehead is primarily determined by the frontal bone, which holds significance for health and aesthetics. This study evaluated the morphology of the frontal bone in different age groups and genders using computed tomography (CT). This cross-sectional study was conducted on CT scan results of 220 patients divided into three age groups: 20-29.27, 29.27-47.54, and 47.54-95 years. The investigation explored the lower and upper angles compared with the Sella-Nasion (SN) line, the maximum frontal projection with Nasion in the SN plan, and the variations in frontal thickness across different angles (15, 30, 45, 60, 75, and 90 degrees) relative to the SN plane. All data were analyzed using R software, considering the significance level p < 0.05. Of 220 patients, 119 were men, and the mean age of the participants was 41.09 ± 18.06 years. The average upper frontal slope (UFS) angle was 56.96 ± 8.17 degrees, which was 59.35 ± 7.92 degrees in females and 54.94 ± 7.86 degrees in males. The mean lower frontal slope (LFS) angle was 86.30 ± 7.96 degrees, which was 90.71 ± 6.67 degrees in females and 82.55 ± 7.00 degrees in males. The average contour nasion (C-N) distance was 7.51 ± 3.72 mm. Also, the frontal thickness at an angle of 15 degrees had the highest value of 13.08 ± 2.68 mm and at 30 degrees had the lowest value of 5.81 ± 1.56 mm. A significant difference was observed between the UFS and LFS among males and females (p < 0.001). Across all age groups, men exhibited a steeper angle, indicating a greater posterior inclination than women. Moreover, males with upper ages reported a significant increase in C-N distance and frontal projection (p < 0.05). Our findings emphasize the importance of considering gender-specific variations in frontal bone structure when planning cosmetic or reconstructive procedures involving the forehead.

Geology of the Golobar and Rumaceo faults, Basque-Cantabrian Pyrenees

ABSTRACT The lateral transition between different styles of deformation is crucial for understanding local-scale structures since it influences orogenic reconstructions at the crustal scale. This is especially important at the westernmost Basque-Cantabrian Pyrenees, where the transition from the thin-skinned Basque-Cantabrian Pyrenees to the thick-skinned Cantabrian Mountains remains a subject of debate. To address this, detailed geological mapping and proper fault characterisation are critical. This research focused on the surface characterisation of the Golobar Fault System, one of the faults located at the transition between the two styles of deformation. The results of this study include not only a detailed geological map of the Golobar Fault System but also its integration with neighbouring seismic sections and well data. This approach enhances the understanding of the deeper portions and lateral thickness variations, thereby providing a more comprehensive understanding of the Golobar area within the regional framework.

Development of a Robot-Assisted Fused Deposition Modeling Process for Enhanced Additive Manufacturing

&lt;div&gt;This work aims to define a novel integration of 6 DOF robots with an extrusion-based 3D printing framework that strengthens the possibility of implementing control and simulation of the system in multiple degrees of freedom. Polylactic acid (PLA) is used as an extrusion material for testing, which is a thermoplastic that is biodegradable and is derived from natural lactic acid found in corn, maize, and the like. To execute the proposed framework a virtual working station for the robot was created in RoboDK. RoboDK interprets G-code from the slicing (Slic3r) software. Further analysis and experiments were performed by FANUC 2000ia 165F Industrial Robot. Different tests were performed to check the dimensional accuracy of the parts (rectangle and cylindrical). When the robot operated at 20% of its maximum speed, a bulginess was observed in the cylindrical part, causing the radius to increase from 1 cm to 1.27 cm and resulting in a thickness variation of 0.27 cm at the bulginess location. However, after optimizing the speed at 35% of its maximum speed, 100% dimensional accuracy was achieved. The integration resulted in collision-free robot and extrusion movement, flexibility, capability of making large parts, and enhanced dimensional accuracy.&lt;/div&gt;

Simulation Study of High-Precision Characterization of MeV Electron Interactions for Advanced Nano-Imaging of Thick Biological Samples and Microchips

The resolution of a mega-electron-volt scanning transmission electron microscope (MeV-STEM) is primarily governed by the properties of the incident electron beam and angular broadening effects that occur within thick biological samples and microchips. A precise understanding and mitigation of these constraints require detailed knowledge of beam emittance, aberrations in the STEM column optics, and energy-dependent elastic and inelastic critical angles of the materials being examined. This simulation study proposes a standardized experimental framework for comprehensively assessing beam intensity, divergence, and size at the sample exit. This framework aims to characterize electron-sample interactions, reconcile discrepancies among analytical models, and validate Monte Carlo (MC) simulations for enhanced predictive accuracy. Our numerical findings demonstrate that precise measurements of these parameters, especially angular broadening, are not only feasible but also essential for optimizing imaging resolution in thick biological samples and microchips. By utilizing an electron source with minimal emittance and tailored beam characteristics, along with amorphous ice and silicon samples as biological proxies and microchip materials, this research seeks to optimize electron beam energy by focusing on parameters to improve the resolution in MeV-STEM/TEM. This optimization is particularly crucial for in situ imaging of thick biological samples and for examining microchip defects with nanometer resolutions. Our ultimate goal is to develop a comprehensive mapping of the minimum electron energy required to achieve a nanoscale resolution, taking into account variations in sample thickness, composition, and imaging mode.

Ocean weather systems on icy moons, with application to Enceladus.

We explore ocean circulation on a rotating icy moon driven by temperature gradients imposed at its upper surface due to the suppression of the freezing point of water with pressure, as might be induced by ice thickness variations on Enceladus. Using high-resolution simulations, we find that eddies dominate the circulation and arise from baroclinic instability, analogous to Earth's weather systems. Multiple alternating jets, resembling those of Jupiter's atmosphere, are sustained by these baroclinic eddies. We establish a theoretical model of the stratification and circulation and present scaling laws for the magnitude of the meridional heat transport. These are tested against numerical simulations. Through identification of key nondimensional numbers, our simplified model is applied to other icy moons. We conclude that baroclinic instability is central to the general circulation of icy moons.

Total retinal thickness is an important factor in evaluating diabetic retinal neurodegeneration

ObjectiveMacular retinal nerve fibre layer (mRNFL) and ganglion cell-inner plexiform layer thickness (GC-IPL) measurements are important markers of diabetic retinal neurodegeneration (DRN). In this cross-sectional study, we aimed to quantify...

Quantifying choroidal and retinal thicknesses variations via optical coherence tomography in different stages of pediatric keratoconus

PurposeKeratoconus (KCN) is characterized by corneal thinning and bulging, leading to vision impairment. Assessing choroidal thickness (CT) in pediatric KCN ( pKCN) patients can provide insights for better understanding and managing the disease. CT may serve as a potential indicator of disease activity in KCN patients. This study aims to evaluate CT and retinal thickness (RT) in different stages of pKCN patients and compare the findings with an age-matched control group.Methods and patientsThis cross-sectional study included patients under 18 years old who met specific criteria. CT and RT was measured in all subjects using an optical coherence tomography device (Spectralis OCT, version 6.0, Heidelberg Engineering, Germany) with enhanced depth imaging mode, without pupil dilation. Mean CT and RT in pKCN was compared with healthy subjects and assessed among different disease grades using the ABCD grading method.ResultsThe study included 125 eyes (66 patients) in the pKCN group and 42 control eyes (21 individuals). Grade 2 KCN showed the highest prevalence at 26.4% (N = 33), while grades 3 and 1 had prevalence rates of 24% (N = 30). CT in all specified areas (all P-values < 0.001), as well as RT in the subfoveal area (P-value < 0.001) and 1500 μm nasal to the fovea (P-value = 0.025), were significantly greater in the pKCN group compared to controls. Furthermore, CT and RT differed significantly among the pKCN grades (P-values < 0.001).ConclusionCT was found to be elevated in pKCN patients, similar to adult KCN cases. CT could potentially serve as a clinical marker for disease activity in pKCN; however, further studies are needed.

Size‐dependent buckling loads of non‐uniform Bernoulli–Euler beams with elastic boundary conditions and thermal effects based on two‐phase local/nonlocal elastic model

AbstractWe present predictive models of the size‐dependent buckling loads of non‐uniform Bernoulli–Euler beams under thermal effects based on the two‐phase local/nonlocal elastic model. The beam ends are assumed to be constrained by elastic springs with translational and rotational stiffness to simulate general boundary conditions. In contrast to most literature in this field, both the bending and thermal deformations of the beams are simultaneously considered to be two‐phase local/nonlocal of two phases, that is, the thermal effect is taken as equivalent to a size‐dependent thermal load. By using the fully equivalent differential form of the local/nonlocal equation with a set of constitutive boundary conditions, the problem is solved numerically with the aid of the generalized differential quadrature method (GDQM). Through conducting validation study, several parametric studies are given for examining the effects of the slope of beams’ thickness variation, nonlocal parameter, and elastically supported conditions on the buckling loads of non‐uniform beams. The results show that constrained stiffness has a drastic influence on the critical bucking loads of the beams. Furthermore, the consideration of the two‐phase thermal load will further reduce the actual buckling load of the beams.

Application of Hybrid Conventional Filter and PVDF-TiO&lt;sub&gt;2&lt;/sub&gt;/SBE Hollow Fibre Membrane for Peat Water Treatment

South Kalimantan-Indonesia is known to have extensive peatlands reaching 15% of a total peatland in Kalimantan. Due to that peat land water is mostly found and claim as abundant water sources. However, based on quality, peat land water has poor characteristic with high natural organic matter content. Therefore, peat water treatment is necessary to treat using effective method such as hybrid conventional filter and membrane using hollow fibre PVDF-TiO2/SBE. This study aims to investigate the variation of media filter thickness and filtration pressure of hollow fibre (HF) PVDF-TiO2/SBE membrane peat water treatment by filtration pre-treatment and HF membrane ultrafiltration. HF PVDF-TiO2/SBE membrane was prepared by wet spinning method using spinneret set up. Hybrid process was divided into two steps: 1) conventional filter as pre-treatment and 2) HF ultrafiltration membrane under cross flow system. The filter media was used in this work is silica sand and activated carbon with varied thickness 30:10 and 10:30 cm. The HF membrane structure was analysed via scanning electron microscopy (SEM) to investigate the membrane morphology. The results show the fabricated HF membrane has a finger like-sponge sandwich structure morphology. In addition, 30:10 cm (silica sand: activated carbon) thickness exhibits TDS and turbidity removal of 92.18 and 61.37%, respectively as conventional filter pre-treatment. In other hand, HF membrane successfully removed TDS and turbidity of peat water up to 98.68% and 92.41% at 2 bar of filtration pressure. The highest permeate flux of HF membrane conducted of 13.055 Kg.m-2.h-1 at 3 bar. Conclusion of this work is the peat water treatment using activated carbon: silica filtration pre-treatment and HF membrane ultrafiltration can provide clean water with maximum turbidity and TDS removal.

Low thickness effect on the properties of Mn-doped ZnO thin films synthesized by sol-gel spin coating technique

In this study, 7% manganese-doped zinc oxide (MZO) thin films with varying low thicknesses were synthesized using the spin coating method. The structural, optical, and morphological properties of MZO films with different film thickness, were systematically investigated. The crystallite structure, superficial morphology, and optical characteristics were analyzed using X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), and ultraviolet–visible spectroscopy (UV-Vis). Structural analysis confirmed that all films exhibit a hexagonal wurtzite phase with a pronounced peak along the c-axis, and slight variation in low thickness significantly affected the structural parameters. The surface morphology demonstrated good uniformity, characterized by rounded grain shapes in the plane, while surface roughness was found to be increased with increasing film thickness. Optical analysis revealed that as the number of coatings increased, both transmittance and band gap energy decreased, accompanied by a redshift in the absorption edge across all samples. This behavior is attributed to light scattering, as well as an increase in the refractive index and dielectric function with visible light energy, influenced by the number of layers and corresponding crystallite size.

EFFECTIVE DOSE ANALYSIS IN ABDOMEN AP EXAMINATION PATIENTS WITH CALDOSE_X VERSION 5.0

This study evaluates radiation dose exposure during diagnostic radiology procedures using X-rays and their potential risks, including cancer, to optimize radiation safety through the CALDose_X software that calculates the absorbed organ dose, effective dose, and cancer risk, according to the lowest possible achievable (ALARA) principle. This study used a quantitative experimental design to evaluate the impact of filter thickness variations on Entrance Surface Air Kerma (ESAK) and effective dose by analyzing data from 54 patients undergoing AP Abdominal X-ray examinations. The results showed that the effective dose to the abdominal organs varied with exposure factors and Focus to Detector Distance (FDD), where the colon wall had the highest sensitivity with doses ranging from 0.030 mSv to 0.126 mSv, followed by the stomach and pancreas. Increasing kV, mAs, and FDD increased the effective dose, emphasizing the importance of careful dose management. This study concluded that exposure factors and FDD affect the effective dose received by the abdominal organs, with recommendations to monitor patient doses, revise national diagnostic reference levels, and establish standard protocols with health authorities. Keywords: CALDose_X, X-ray Exposure Factor, patient dose, ESAK, Effective Dose, Abdomen AP.