Element Analysis Research Articles

Genome-wide identification of HIPP and mechanism of SlHIPP4/7/9/21/26/32 mediated phytohormones response to Cd, osmotic, and salt stresses in tomato

Heavy-metal-associated isoprenylated plant proteins (HIPPs) contributed to abiotic tolerance in vascular plants. Up to now, the HIPP gene family of tomato (Solanum lycopersicum L.) had not been thoroughly understood. In the present study, 34 SlHIPP genes were identified from the tomato genome using the Hidden Markov Model (HMM). The phylogenetic analysis revealed that the evolution of SlHIPPs was highly conserved. The cis-acting element analysis indicated that SlHIPP genes might be involved in phytohormones and abiotic stresses. We constructed venn diagram with 17 genes containing stress-related motifs as well as 15 genes and 19 genes expressing in leaves and roots in RNA-seq data, suggesting that SlHIPP4/7/9/21/26/32 were selected as candidate genes for study. The quantitative real-time PCR (qRT-PCR) analysis showed that 6 candidate genes were indicated to be involved in osmotic and salt stress tolerance and SlHIPP7/21/26/32 responded to cadmium (Cd) tolerance. The virus-induced silencing of 6 candidate genes caused growth inhibition in stress conditions, further illustrating that 6 candidate genes played a positive role in abiotic conditions. Importantly, the phytohormone analysis implied that 6 candidate genes mediated abscisic acid (ABA), salicylic acid (SA), gibberellin (GA3), auxin (IAA), or methyl jasmonate (MeJA) responses to Cd, osmotic, or salt stress tolerance. These findings indicated that SlHIPP4/7/9/21/26/32 were key regulators of abiotic stress responses in tomato seedlings, functioning through multiple phytohormone pathways.

Reliable simulation analysis for high-temperature inrush water hazard based on the digital twin model of tunnel geological environment

In complex mountainous terrains, tunnel construction faces unique challenges from high-temperature water inrush hazards, a systemic risk arising from the interplay of stress, seepage, and temperature fields. Traditional simulation methods, focusing on isolated disaster scenarios, fall short in addressing the multifaceted nature of these risks due to geological ambiguity and data incompleteness. Digital twin technology presents an effective solution to these challenges; however, its core challenge lies in how to utilize digital twin technology for data-model-co-driven simulation analysis of coupled multi-physical fields in situations of incomplete data. This paper introduces a digital twin paradigm for the simulation analysis of water inrush, which significantly enhances efficiency and accuracy through the integration of advanced machine learning and finite element analysis techniques. Specifically, this is achieved by combining a high-precision geological modeling method based on Gaussian Processes (GP) with a parameter calibration method through Gaussian Process-Differential Evolution (GP-DE) back-analysis. Firstly, a voxel structure is utilized to integrate the multi-field attribute features of the tunnel environment. Secondly, through the integration of multi-source advanced geological prediction data, we construct a dynamic digital twin model of the tunnel environment leveraging machine learning techniques. To overcome the issue of low modeling accuracy, the GP is employed, enhancing the exploitation of latent information within multi-source geophysical data. Lastly, we utilize the GP-DE back-analysis method to calibrate the parameters of the tunnel environment, thereby enhancing the precision and reliability of water inrush simulations. The method has been validated through application to a section of an ultra-high-temperature water inrush tunnel in China, featuring a burial depth of 230 meters. The accuracy of the method is corroborated by the monitoring data from the tunnel, supporting dynamic optimization design and safety prevention measures during construction.

Parametric assessment of new O-ring bracing performance under progressive collapse using nonlinear analysis

Progressive collapse poses a significant threat to the structural integrity of buildings under extreme loading conditions, necessitating robust design strategies to mitigate its effects. This paper extends prior research by the same authors on the performance of O-ring bracing during progressive collapse in comparison with other bracing systems. The primary objective is to investigate various design parameters and configurations that optimize the performance of O-ring bracing systems under progressive collapse scenarios through a comprehensive parametric assessment. Nonlinear finite element analysis is employed to evaluate different design parameters, including the size, shape, orientation, and strength of O-ring braced sections, and connection detailing. These factors are assessed for their influence on structural strength, stiffness, and ductility. The parametric study identifies configurations that significantly enhance structural resilience, providing recommendations for future designs aimed at preventing progressive collapse in O-ring braced frames. Data AvailabilityAll data is available from the Authors upon reasonable request.

A comprehensive finite element framework for modeling of PEX-Al-PEX composite pipes

While PEX-Al-PEX composite pipes are widely used in various applications, suitable tools and models for simulating their performance under different working conditions have not been made available. Therefore, the present study aims to develop a comprehensive finite element model to study the behavior of PEX-AL-PEX pipes at different temperatures and strain-rates. To achieve this, the properties of the pipe layers have been obtained for different temperature and strain-rate values through experimental tests. To assess the accuracy of the developed finite element model, the lateral compression and the split-disc tension tests have been performed under different conditions using both experimental and finite element analysis methods, and their results have been compared. The proposed model can be used to study the behavior of PEX-AL-PEX pipes with different materials and geometries in various conditions and applications, as well as for optimizing the design and manufacturing of these pipes.

PM flux-reversal machine for wind energy application

Currently, attempts are being made to harness wind energy by means of non-conventional electrical machines such as flux reversal machines (FRM). The main advantage of the FRM, when compared with existing synchronous generators (SG), is that all the active parts like PMs and armature windings are mounted on the stator part, whereas leaving the rotor has simple and robust. In this study, the three-phase 6/8-pole flux reversal generators (FRGs) are selected, sized, designed, and analyzed using finite element analysis (FEA). The working principle, choice of stator and rotor poles, and machine design dimensions evaluation (analytical sizing procedure), as well as relevant performance details are discussed in this paper. This study is used to analyze, a popular 6/8 pole, 0.8 kW, 50 Hz, and examine the suitability for the wind energy applications in terms of torque and power density, torque ripple, power factor, and cogging torque under 2D finite element analysis (FEA). The analysis provides an update on the current state-of-the-art and as well as future thrust areas of research necessary to bridge the gap on what is still desired for the practical application of FRMs for wind energy.

Study on stress concentration and fatigue life of tubing with slip indentation

The indentation caused by slip on the outer wall of tubing is a significant contributor to stress concentration and, consequently, fatigue failure in the tubing string. Through an analysis of the interaction between slips and tubing, a mathematical model to predict slip-tubing interaction and slip crushing load is formulated, accounting for external pressure, internal pressure, and axial forces. On this basis, the influence factors and influence rules of slip crushing load are studied, and three-dimensional yield surface and tri-axial stress ellipse of tubing are investigated, considering different transverse load factors and design factors. To accurately forecast the fatigue life of tubing subjected to slip indentation, two models are established: one for fatigue life prediction and the other for tubing string vibration. In order to quantitatively assess the stress concentration arising from slip indentation, a finite element model of tubing featuring slip indentation is established. Finite element analysis reveals that stress concentration and non-uniformity are evident in the vicinity of slip indentation, with their severity intensifying as the indentation depth grows. The initial step in assessing fatigue life involves fatigue life tests on tubing material subjected to varying stress levels. Subsequently, a case study is conducted and the variations of wellhead pressure and axial stress are evaluated. Fatigue life analysis reveals that the fatigue life is notably sensitive to variations in stress amplitude and slip indentation depth. An increase in the magnitude of alternating stress and the depth of slip indentation will result in a significant reduction in the fatigue lifespan. The methodologies employed in this research, along with the resulting findings, offer a robust theoretical framework and a solid practical basis for forecasting and managing stress concentration and fatigue durability in tubing affected by slip indentation.

Compressive and Bending Properties of 3D-Printed Wood/PLA Composites with Re-Entrant Honeycomb Core

This study investigates the mechanical behavior of sandwich structures comprising a re-entrant honeycomb core structure created using wood/polylactic acid (PLA) filaments via fused deposition modeling (FDM) technology. The sandwich structures were manufactured with different face layer thicknesses (0 mm, 0.8 mm, and 1.6 mm) and various core topologies. Material characterizations included bending tests, compressive tests, and finite element analysis (FEA) to identify stress concentration areas. In-plane and out-of-plane re-entrant honeycomb core structure specimens were tested to examine the bending properties. In addition, flatwise and edgewise compressive tests were performed to investigate the structures' compressive properties. Furthermore, the modulus of elasticity for each specimen was determined using the finite element technique (FEM). The results reveal that increasing the thickness of the face layer significantly enhances the structure's resistance to bending forces. Furthermore, specimens with an in-plane orientation demonstrated better bending strength compared to those with an out-of-plane orientation due to increased material underloading. In flatwise compressive tests, specimens without a face layer exhibited the highest strength, attributed to their greater displacement. In contrast, edgewise compressive tests showed significant buckling behavior of the face sheet, the maximum stress increased proportionally with the thickness of the face layer, reaching its peak at a skin thickness of 1.6 mm. The findings are validated by ANSYS analysis, which closely mirrors the experimental results, providing insight into flexural modulus, modulus of elasticity, and stress concentration. These findings indicate that architected core structures could be efficiently utilized to improve bending/compressive characteristics and failure mechanisms, providing valuable insights into the mechanical response of sandwich structures for different industrial applications.

MXene@Wood composite with absorption-dominated electromagnetic interference shielding performance through structural modification

Wood-based materials possess unique porous structure that are sustainable and green, showing great potential in many applications. Herein, MXene@Wood composites were prepared for electromagnetic interference shielding and thermal insulation, and their pore structure is monitored by compression of wood. Benefiting from the heterogeneous interface between MXene and the wood surface to enhance interfacial polarization, MXene@Wood presents a superior impedance match in cross-section compared to tangential-section. In the cross-section, MXene@Wood at a 30 % compression ratio achieves an absorption coefficient of 0.73 and a shielding effectiveness of 41.78 dB. After a 30 % compression ratio, MXene@Wood in cross-section achieves an absorption coefficient of 0.73 and a shielding effectiveness of 41.78 dB, it also exhibits wave absorption performance with a minimum reflection loss of −15.11 dB at 2 mm, meeting the commercial requirements. The effect of the pore structure of wood on shielding performance is further verified by finite element analysis. Furthermore, MXene@Wood also demonstrates excellent thermal insulation properties benefit to the reduced gas-phase heat transfer. This sustainable composite with electromagnetic shielding performance and thermal insulation properties largely expands the application area of wood.

Interfacial microstructure and fracture mechanism of Cu/Al composite plate jointing process assisted by pulsed current-melted Al spheres: Finite element analysis and experimental studies

In this work, a novel method based on pulsed-current-assisted vacuum sintering processes was employed to fabricate the Cu/Al laminated metal composites (LMCs) with outstanding mechanical properties. The microstructural evolution, interfacial characteristics, phase composition, mechanical properties, and fracture behavior of Cu/Al composites prepared by the melted Al spheres induced with high-frequency pulsed current were investigated. Results show that robust interfacial bonding without micropores and cracks, and the grain structure consists mainly of recrystallized and substructured grains characterized by high angular grain boundaries. Meanwhile, interfacial analysis identifies melted Al and Al2Cu phases within the transition layer, exhibiting distinctive features such as "Al+Al2Cu" corrugated interfaces and island eutectic structures. Additionally, mechanical properties demonstrate superior strength (210 ± 13MPa) and elongation (27% ± 0.7%) in specimens with corrugated interfaces compared to those with flat interfaces. Finite element analysis further elucidates stress redistribution and fracture behavior, emphasizing the enhanced coordinated deformation in specimens featuring corrugated interfaces. These findings underscore the significance of interface engineering and microstructural refinement in optimizing the mechanical performance of Cu/Al composite materials, offering valuable insights for their application in diverse engineering domains.

A micromechanics-based artificial neural networks model for rapid prediction of mechanical response in short fiber reinforced rubber composites

The complex microstructural characteristics inherent in short fiber reinforced rubber composites (SFRRCs) impose considerable computational burdens in predicting the mechanical behavior of such composite materials. To address this challenge, this research extends the applicability of the homogeneous model predicated on the orientation averaging method to encompass composite materials featuring hyperelastic matrices. Combined with finite element method, a comprehensive mechanical response database encompassing various volume fractions and fiber orientation distributions is established. Leveraging this database, a micromechanics-based artificial neural network (ANN) model is meticulously designed to rapidly predict the mechanical response of SFRRCs across varying volume fractions and fiber orientation distributions, utilizing a fixed strain step strategy. To ascertain the efficacy and precision of the developed ANN model, representative volume elements portraying both planar and three-dimensional random distributions of composites are constructed and subjected to finite element analysis. Results indicate that the predicted outcomes from the ANN model align closely with finite element calculations within a certain strain range, while significantly reducing computational costs.

Transformer-based settlement prediction model of pile composite foundation under embankment loading

Pile composite foundation (PCF) is a common method for treating weak foundations, with settlement being the primary indicator in its design. However, accurately and quickly obtaining PCF settlement remains challenging. This study proposes a transformer-based PCF settlement prediction model under embankment loads (PCFFormer model), which enables efficient and accurate predictions of PCF settlement across various embankment environments and pile schemes. To establish and validate the data-driven PCFFormer model, this study also developed an automatic modeling and data processing program for PCF based on the Abaqus platform. Furthermore, a large-scale dataset of PCF finite element models under embankment loads was constructed and released, which is currently the largest publicly available dataset of PCF finite element models. Additionally, this study introduces a data augmentation method that fully utilizes the finite element analysis process data, significantly improving the efficiency of creating the PCF settlement dataset. By comparing the PCF settlement predicted by the PCFFormer model with the results of finite element analysis and the predictions of other machine learning methods, the accuracy and superiority of the PCFFormer model are demonstrated. The study further discusses the impact of missing individual parameters in cushion and soil layers on the prediction accuracy of the PCFFormer model.

Modelling and Finite Element Analysis of Structural Modifications in Brake Pad and Disc to Suppress Squeal

Modelling and Finite Element Analysis of Structural Modifications in Brake Pad and Disc to Suppress Squeal

3D package thermal analysis and thermal optimization

3D packaging mainly uses TSVs (Through Silicon via) to vertically interconnect multiple chips, achieving the purpose of signal transmission and electrical connection. As a popular advanced packaging method, its research is of great significance. Although stacked chips can achieve stronger performance in smaller spaces, they can also cause a series of reliability issues, among which thermal stress and warping due to differences in the thermal expansion coefficients of materials can even lead to chip failure. Therefore, it is highly valuable to simulate and analyze the entire 3D packaging model.In this study, the thermal stress and deformation of the whole three-dimensional package model were simulated by finite element analysis. The results showed that there were significant stress and deformation effects at the joint of the TSV structure at normal temperature, and the stress and deformation reached 209.99MPa and 0.0018519mm, respectively. After that, the temperature of the double-sided package system containing 3D package under electrothermal coupling conditions was optimized by heat dissipation design, which verified the ‘quantity first’ scheme of heat dissipation fins and reduced the temperature by 40%.

Design of flexible polyimide-based serpentine EMG sensor for AI-enabled fatigue detection in construction

Physical fatigue and musculoskeletal disorders are critical health issues for construction workers, stemming from repetitive motions, heavy lifting, and awkward postures. These factors compromise worker well-being, productivity, and safety while increasing the risk of accidents and long-term health problems. Recent advancements in wearable health monitoring technology offer potential solutions, but current sensors encounter significant challenges in the dynamic construction environment. These include inadequate skin contact, increased contact impedance, and vulnerability to motion artifacts all of which degrade signal quality and reduce the accuracy of fatigue detection. This paper develops a fractal-based, flexible sensor for enhanced adaptability and accurate fatigue estimation. Finite element analysis compared five space-filling designs, with the serpentine curve exhibiting the highest contact area and lowest strain, making it the preferred choice for fabrication. Evaluations demonstrated significant improvements in signal-to-noise ratio (SNR) and motion artifact reduction, with the newly developed sensor achieving a 37 % to 59 % SNR improvement over commercial electrodes across different muscle groups. The developed flexible sensor was integrated with a fatigue-detecting framework based on a vision transformer model which provided an average accuracy of 87 % for fatigue detection. The developed sensor significantly enhances EMG signal quality and reliability, promising improved health monitoring and safety for construction workers.

Research on Stiffness Analysis and Technology of the Heavy Spidle Top

Background: The spindle top is an important component used to withstand the shaft workpiece on machine tools so that the spindle can meet high efficiency and high precision requirements. However, the selection principles under various load conditions are not stipulated in use. In addition, material selection, manufacturing, heat treatment technology, etc., are of practical significance for the production of high hardness, high wear resistance, and high precision spindle tops. Objectives: The spindle top type, material selection principles, heat treatment, cold working, and other manufacturing processes are given. Provide a reference for highperformance and top-notch design and manufacturing. Methods: The model of the spindle top will be created in UG software, then using ANSYS finite element analysis software to analyze stiffness of spindle top whose height-to-diameter ratios are 1:4 and 1:7 types in a variety of different load cases. The design and manufacturing process of the spindle top is analyzed and expounded from the selection and performance comparison of metal materials, heat treatment of different materials, cold manufacturing technology, and other aspects. Results: The deformation laws of different types of spindle tops are obtained. According to the deformation regular, find the selection principle of height to diameter ratio of spindle top. The defects that are easy to occur in the technology are obtained and the preventive and solution measures are put forward. Conclusion: According to the deformation regular, find the selection principle of height to diameter ratio of spindle top. The material selection, heat treatment technology, and other technical research on the spindle top provide the necessary basis for the production of the spindle top.

Designing and additive manufacturing of biomimetic interpenetrating phase zirconia-resin composite dental restorations with TPMS structure

Zirconia and resin are the most commonly utilized materials in dental restorations. However, zirconia presents significant wear on opposing teeth, whereas resin materials have low wear resistance and mechanical performances. A zirconia-resin interpenetrating phase composite (IPC) dental restoration was designed and fabricated using 3D printing and vacuum infiltration processes, incorporating zirconia scaffolds with triply periodic minimal surfaces (TPMS) structures. The mechanical and tribological performances of the IPCs were investigated through compressive and tribological experiments and finite element analysis, elucidating the influence of zirconia volumetric fraction. Results showed that IPCs exhibit excellent mechanical and tribological compatibilities, which can reduce the damage and wear of the antagonistic teeth. This designing and manufacturing strategy enables the IPC restorations with promising applications in dentistry.

Integrative transcriptome and metabolome analyses reveal the mechanism of melatonin in delaying postharvest senescence in cowpeas

Rapid postharvest senescence and quality deterioration severely limit logistics of cowpeas. Melatonin (MEL) is a pivotal bioactive molecule that can modulate multiple physiological attributes in plants. In this study, physiological, transcriptomic and metabolomic analyses were conducted to explore the effects of exogenous MEL on cowpea senescence and its underlying mechanisms. Physiological results showed that 100 μM MEL treatment maintained sensory quality (greeness, firmness and soluble solids content), reduced weight loss as well as inhibited the degradation of chlorophyll (Chl) and protopectin. Preservation of color and firmness in cowpeas was greatly attributed to inhibition of expression of genes related to Chl and cell wall metabolism, which was based on a transcriptomic analysis. Integrated transcriptomic and metabolomic analyses revealed that MEL promoted transcription of genes associated with amino acid and carbohydrate metabolism, resulting in the accumulation of amino acid and sugar metabolites. Additionally, by integrating transcription factor-binding site analysis with cis-acting element analysis, we constructed a regulatory network of transcription factors underlying MEL-mediated antisenescence. The present study found a series of potential candidate genes and metabolites involved in regulating senescence process and provided an insight into improving postharvest quality of cowpeas.

Identification and analysis of NAC genes related to S-alk(en)yl cysteine sulfoxides (CSOs) biosynthesis in Onion (Allium cepa L.)

The NAC family, a specific type of plant transcription factor, has been identified in various horticultural crops. Nevertheless, the comprehensive bioinformatics and biological function of the NAC family in onion remain unclear. S-alk(en)yl cysteine sulfoxides (CSOs) are crucial for onion flavor quality and health effects. There is a growing interest in studying the mechanism of CSOs synthesis regulation in onions due to the increased realization of their potential value. In this study, sixty members of the NAC family was identified based on transcriptomic data. These transcription factors were distributed on eight chromosomes of onion. Phylogenetic tree showed that AcNAC members were divided into three groups with similar conserved protein motifs. Cis-acting elements analysis showed that the promoter of AcNACs contained a large number of photoresponsive and hormone-responsive elements. The correlation analysis of the expression patterns of transcriptome data selected 18 AcNACs that might regulate the synthesis of CSOs. Two putative NAC transcription factors, AcNAC12 and AcNAC17, were speculated as potential regulators in the biosynthesis of CSOs in onions through the analysis of expression patterns of AcNAC genes across different growth stages and cultivars, as well as Y1H, dual luciferase, GUS staining, and gene suppression experiments. This study aims to provide suggestions and research directions for further investigation of the functions of AcNAC family members and regulatory pathways for CSO biosynthesis.

Developing a Virtual Model of the Rhesus Macaque Inner Ear

A virtual model of the rhesus macaque inner ear was created in the present study. Rhesus macaques have been valuable in cochlear research; however, their high cost prompts a need for alternative methods. Finite Element (FE) analysis offers a promising solution by enabling detailed simulations of the inner ear. This study employs FE analysis to create a virtual model of the rhesus macaque’s inner ear, reconstructed from MRI scans, to explore how cochlear implants (CIs) impact residual hearing loss. Harmonic-acoustic simulations of sound wave transmission indicate that CIs have minor effects on the displacement of the basilar membrane and thus minimally impact residual hearing loss post-implantation, but stiffening of the round window membrane worsens this effect. While the rhesus macaque FE model presented in this study shows some promise, its potential applications will require further validation through additional simulations and experimental studies.

Mitigating Low-Speed Crawling and Jitter in Telescopic Hydraulic Cylinders through Stick-Slip Dynamics Analysis and Friction Reduction Strategies

Abstract This study investigates the mechanisms of jittering in telescopic cylinders and proposes effective mitigation strategies. The focus is on the dynamic behavior of hydraulic cylinders under low-speed conditions, particularly the stick-slip phenomenon. Through finite element analysis using Abaqus and tribological tests, the impact of various factors on the friction and wear properties of cylinder components is examined. Findings reveal that optimizing the average friction coefficient, stick-slip amplitude, and stick-slip time can significantly reduce jitter and creep in hydraulic cylinders. The results provide valuable insights for improving the performance and longevity of hydraulic systems in engineering machinery.