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Most existing studies about line balancing problems mainly focus on disassembly and assembly separately, which rarely integrate these two modes into a system. However, as critical activities in the remanufacturing field, assembly and disassembly share many similarities, such as working tools and processing sequence. Thus, this paper proposes a multi-objective hybrid production line balancing problem with a fixed number of workstations (HPLBP-FNW) considering disassembly and assembly to optimise cycle time, total cost, and workload smoothness simultaneously. And a novel Pareto-based hybrid genetic simulated annealing algorithm (PB-HGSA) is designed to solve it. In PB-HGSA, the two-point crossover and hybrid mutation operator are proposed to produce potential non-dominated solutions (NDSs). Then, a local search method based on a parallel simulated annealing algorithm is designed for providing a depth search around the NDSs to balance the global and local search ability. Numerical results by comparing PB-HGSA with the well-known algorithms verify the effectiveness of PB-HGSA in solving HPLBP-FNW. Moreover, the managerial insights based on a case study are given to inspire enterprise companies to consider hybrid production line in the remanufacturing process, which is beneficial to reduce the cycle time and total cost and improve the service life of the equipment. [ABSTRACT FROM AUTHOR]

VO2-based thermochromic coatings have gained much attention in temperature-adaptive smart windows, and constructing multilayer film structures is the main way to obtain high thermochromic performances. Based on the self-developed objective-orientated automatic optimization code, the present research realized customized designs of thermochromic multilayer coatings composed of VO2, TiO2, and SiO2 from the objectives of visible luminance (Tlum) and solar light modulation (ΔTsol). The TiO2/VO2/s, VO2/TiO2/s, TiO2/VO2/TiO2/s, and SiO2/TiO2/VO2/TiO2/s (s denotes substrate) multilayer film systems were then prepared by magnetron sputtering and vacuum controllable heating, with their structures, insulator-metallic transition, and thermochromic properties being carefully studied. The result showed that the best trade-off between high Tlum and high ΔTsol was achieved for these film assemblies, and solar light modulation was mainly limited at the near-IR wavelength region of the solar spectrum, with the difference between cool- and hot-state Tlum being greatly reduced. In the case of the four-layer SiO2/TiO2/VO2/TiO2/s, very high average Tlum (60%) and high ΔTsol (14%) were obtained. A 100 × 100 mm2 of the SiO2/TiO2/VO2/TiO2/s was also prepared, and it showed an obvious temperature adjustment, and the service life can last for 14 years under normal weather conditions. Not limited to the prepared multilayer film systems, the methodology used here is also suitable for the fast development of other multilayer film systems. [ABSTRACT FROM AUTHOR]

Materials for additive manufacturing (AM), such as PLA and PEEK, are often used in biomedical applications, which involve interaction with liquid media. Consequently, the degradation process is a part of the service life of such polymers that can alter their mechanical response due to gradual changes in materials' properties. Studying the behaviour of polymers in such environments is thus important for the prediction of the mechanical performance of biomedical devices. This paper examines the process of accelerated degradation of AM PLA and PEEK samples in saline solution and distilled water at elevated temperatures. An analysis of changes in mechanical properties, such as tensile strength and density, of PLA and PEEK with the immersion time was performed. The influence of heat treatment on the degradation process was investigated. It was found that the degradation rate of PLA in distilled water was higher than in NaCl. The trends in density changes measured with hydrostatic weighing correspond to those in the strength properties of the studied samples. [ABSTRACT FROM AUTHOR]

Textile reinforced mortars (TRM) are materials whose mechanical behavior has been extensively investigated during the last few years. However, studies on the behavior of these materials after exposure to various aggressive environments are still limited and, hence, their performance during their entire service life remains to be determined. The present study contributes to the knowledge pool regarding the behavior of concrete specimens furnished with TRM overlays post their exposure to various harsh environments, specifically through the analysis of shear bond tests. More specifically, 120 concrete substrates were reinforced with one and two layers of carbon textile which were embedded into a high and a low strength cementitious mortar and exposed to various harsh environments (carbonation, chlorides, carbonation and chlorides, different number of freeze–thaw cycles). It was concluded that: (i) a reduction of more than 25% is possible regarding failure stress; (ii) the number of textile layers plays an important role in TRM‐concrete bond behavior; and (iii) the influence of mortar strength is limited. [ABSTRACT FROM AUTHOR]

Multicomponent solid solution ceramics have attracted extensive attention for their superior ablation resistance and high-temperature resistance, which are expected to extend the service life of carbon/carbon (C/C) composites under an ablation environment above 2000 °C. Herein, we synthesized (Hf ⅓ Zr ⅓ Ta ⅓)C solid solution ceramic powders via carbothermal reduction. Then a dense (Hf ⅓ Zr ⅓ Ta ⅓)C solid solution ceramic coating was deposited on SiC-coated C/C composites by supersonic atmospheric plasma spraying. The coated samples exhibited a low linear ablation rate of −0.61 μm/s after ablation for 120 s, mainly associated with the formation of a compact oxide scale consisting of (Hf, Zr) 6 Ta 2 O 17 and (Hf, Zr)O 2. The refractory (Hf, Zr)O 2 skeleton structure possessed good thermal endurance, and the Ta-rich oxide melt filled the defects of the skeleton. [ABSTRACT FROM AUTHOR]

A microwave-hot air belt dryer (MHABD) showed high specific energy consumption (SEC) due to its limited material processing capacity and extended drying time. Thus, this research presents the development and performance evaluation of an industrial microwave-hot air belt dryer (IMHABD) for drying Namdokmai Sithong mango slices. The IMHABD system, optimized using the COMSOL Multiphysics program, features a 0.9 m × 4.08 m × 0.5 m chamber with 36 magnetrons having a maximum microwave power of 28,800 W (each magnetron produces 800 W) at a frequency of 2,450 MHz. Two drying methods were studied, step-down microwave power drying (IMHABD-S) and constant microwave power drying (IMHABD-C). IMHABD-S, with a power range of 150–350 W combined with hot air at 65 °C, outperformed IMHABD-C, delivering enhanced drying rates, improved color attributes, and reduced shrinkage, along with decreased hardness and toughness values. All dried slices had a water activity lower than 0.6. An IMHABD-S operated at 350 W for 1.5 h showed the lowest SEC. Economic analysis revealed strong support for the IMHABD process, with a net present value (NPV) of 13,647 USD, an internal rate of return (IRR) of 15%, and a 4.95-year payback with a 10-year service life, highlighting its technical efficacy and economic viability for mango drying applications. [ABSTRACT FROM AUTHOR]

The formation and distribution of residual stress during the micro-milling process significantly affect the crack resistance and service life of alumina bioceramics. This study aims to optimize the surface residual stress distribution by adjusting machining parameters, thereby improving the machining quality of alumina ceramics. A three-dimensional finite element model of alumina bioceramics was developed, and numerical simulations were conducted to analyze the effects of feed per tooth, cutting depth, and spindle speed on temperature and residual stress. The study further explores the patterns of residual stress variation. The results show that both surface temperature and residual tensile stress exhibit systematic trends with parameter changes. Specifically, surface residual tensile stress increases with cutting depth initially but decreases sharply once the cutting depth exceeds 25 μm. Residual tensile stress increases with spindle speed, reaching its peak at 21,000 r/min before stabilizing. Additionally, the residual tensile stress rises with feed per tooth at first but gradually declines when the value exceeds 25 μm/z. This research reveals the mechanisms by which micro-milling parameters influence surface temperature and residual stress in alumina bioceramics, providing theoretical guidance for optimizing micro-milling processes. The findings can also be extended to the micro-milling of other hard-to-machine materials, offering broad engineering application potential. [ABSTRACT FROM AUTHOR]

This study contributes to the fields of nondestructive testing (NDT) and structural health monitoring (SHM), which are pivotal for extending the service life of infrastructure and aligning with sustainability goals in construction. The study emphasizes an advanced application of the deformation area difference (DAD) Method, focusing on the comparative analysis of curvature lines derived from photogrammetry‐assisted deflection measurements and direct strain measurements. The novel strain area difference (SAD) method is presented. The research includes numerical simulations and practical experiments. A laboratory experiment with a steel beam demonstrates the method's effectiveness by comparing curvature lines from strain and deflection data. Additionally, an on‐site application on a composite bridge using photogrammetry and drone technology is described with a comparative numerical analysis. The investigations' results shed light on the potential of integrating diverse data sources in NDT/SHM practices. For instance, the integration of deflection measurements and strain measurements for SHM. The comparative analysis provides crucial insights into the accuracy and applicability of the DAD and SAD method in various structural scenarios, improving the precision of condition assessments in reinforced concrete structures. The findings have significant implications for the sustainable maintenance and operation of infrastructure. They support efficient decision‐making in the maintenance and repair of structures, contributing to their longevity and reducing the need for extensive interventions. They present a robust framework for decision‐making in predictive maintenance. [ABSTRACT FROM AUTHOR]

The phenomenon of overweight vehicles severely threatens traffic safety and the service life of transportation infrastructure. Rapid and effective identification of overweight vehicles is of significant importance for maintaining the healthy operation of highways and bridges and ensuring the safety of people's lives and property. With the problems of high cost and low efficiency, the traditional vehicle weighing systems can only meet some of the requirements of different scenarios. The development of artificial intelligence technologies, especially deep learning, has greatly enhanced the accuracy and efficiency of computer vision. To this end, the paper proposes a method using computer vision and deep learning for the non‐contact identification of overweight vehicles. By constructing two deep learning models and combining them with the vehicle vibration model and relevant specifications, the weight and maximum allowable weight of the vehicle are obtained to make a comparison for determining overweight. Experimental verification was performed using a two‐axle vehicle as an illustrative example, and the results demonstrate that the proposed method exhibits excellent feasibility and effectiveness. It shows significant potential in real‐world scenarios, laying a research foundation for practical engineering applications. Additionally, it provides a reference for the governance and decision‐making of overweight issues for relevant authorities. [ABSTRACT FROM AUTHOR]

Scratches and cracks in steel severely affect its service life and performance. However, owing to the irregular shapes and sizes of steel surface defects, defects within the same class may be different, whereas defects between classes may be similar. Existing methods focus only on spatial information, resulting in low detection accuracy. To alleviate these problems, this paper proposes the ECDY (EIFEM CARAFE DyHead) network to enhance the detection capability of steel defects. We first design a feature extraction module that focuses on the edge information of feature contours. This module uses the Sobel operator to extract the edge information of a feature and fuses it with the overall spatial information so that richer semantic information can be obtained. The module has improved accuracy in the YOLOv5, YOLOv8, and YOLOv10 versions, and uses fewer parameters and calculations. In particular, in YOLOv8x, mAP@0.5 increased by 2.5%, and the number of parameters was reduced by 12.4 M. Second, to retain the detailed information in the feature pyramid, and to better reconstruct features, we choose the content-aware reassembly feature method (CARAFE) as the upsampling method. Finally, the detection head was replaced with a dynamic unified detection head (DyHead) to adapt to different defect sizes and different task requirements. Compared with YOLOv8s, the proposed method improves precision by 1.6%, recall by 4%, and mAP@0.5 by 4%. This value is 4.2% higher than the mAP@0.5 of the current SOTA model RT-DETR-L in the field of object detection and has 23.2 M fewer parameters. [ABSTRACT FROM AUTHOR]

The incorporation of self‐healing properties to repair scratches (or other minor damage) has revolutionized the coating industry by increasing service life, sustainability, and optical appearance. This work addresses challenges with the robustness of self‐healing coatings through the inclusion of surface‐tethered covalently adaptable networks (CANs). Surface‐initiated polymerization is combined with spray‐coating to deposit polymers to produce coatings with reversible crosslinks to the tethered chains. These robust coatings are based on reversible vinylogous urethane bonds using 2‐(acetoacetoxy)ethyl methacrylate‐based polymers and tris(2‐aminoethyl) amine (TREN). Here, TREN enables reversible covalent bonding between the spray‐coated and surface‐tethered polymers. Without this polymer brush layer, the physisorbed CAN coatings fail to self‐heal completely, are labile to solvent, and exhibit shear delamination upon scratching. The utility of this tethered coating approach is highlighted through its ability to autonomously self‐heal incisions within seconds at elevated temperatures, or more steadily under ambient conditions. The key to these advancements is the use of polymer brushes as a primer layer to attach the CAN to enhance healing and improve the environmental robustness of the coating. [ABSTRACT FROM AUTHOR]

Translation abstract Rebinding CO2 in calcium silicate units through recarbonationCalcium silicate units (CSU) are manufactured using burnt lime. When installed in contact with air, CSU absorb more than 3 % of their own weight in CO2 from the air and store it permanently in the structure. An equal amount of CO2 was previously released during the production of burnt lime. This reabsorption is known as recarbonation. This article is based on the examination of around 2 t of masonry and documents this CO2 absorption. The data presented allows the conclusion that CSU usually recarbonate in contact with air within 50–60 years. As the service life of solid buildings generally exceeds 60 years by far, the simplified assumption of 95 % recarbonation at the end of the utilisation phase seems appropriate. The exact amount of CO2 reabsorption depends on the raw materials and the quantities used. It can therefore be taken into account directly in life cycle assessments. In EPD the amount of CO2 rebound for the use phase B1 is specified. Plasters, panels, coatings, etc. influence the recarbonation of wall‐building materials and must be taken into account in the LCA for constructions with CSU. [ABSTRACT FROM AUTHOR]

Since asphalt pavement bleeding and raveling are significant threats to road safety, comfort, and service life, timely and accurate detection of them is desirable and cost-effective to develop pavement maintenance programs. Moreover, due to the fact that both of these distresses (i.e., raveling and bleeding) affect the texture of pavements, simultaneous classification of these distresses can provoke challenges. Thus, this study explores efficient texture analysis of 2D images for bleeding and raveling detection using tree-based ensemble methods. To this end, two scenarios of feature extraction are taken into account using Histogram Equalization (HE), Local Binary Pattern (LBP), and Gray-Level Co-occurrence Matrix (GLCM) techniques. Based on these two feature sets, four tree-based ensemble methods were evaluated for classifying the three classes of Bleeding, Raveling, and No-Bleeding & No-Raveling. The results confirmed that Feature Set B which derived from the integration of HE-GLCM and LBP-GLCM feature extraction provided the most favorable outcome, and gained the high performance of F1-Score ≅ 97 %. Finally, Convolutional Neural Network (CNN) models were constructed using the collected dataset and compared to the proposed method. [ABSTRACT FROM AUTHOR]

Phthalic acid esters (PAEs) are often added to plastics to enhance elasticity, transparency, durability and prolong service life as a kind of plasticizer. However, they are not chemically bonded to polymers and are difficult to degrade, which makes it easy for them to release into the environment and enter the human body from various potential sources. This results in environmental pollution and poses health risks. In order to protect ecosystem, ensure food safety and prevent disease, there is an urgent need for sensors that can achieve point-of-care detection of PAEs. Optical sensors have advantages of simplicity, portability and low cost, and have been widely applied to the detection of PAEs. In this review, we focus on introducing the recent advancements and trends in optical sensors for detection of PAEs represented by colorimetric (CL) sensors, fluorescence (FL) sensors and surface-enhanced Raman scattering (SERS) platform. Based on recognition strategies (e.g., label-free, aptamer, molecularly imprinted polymer, antibody and enzyme), the significant achievements of these optical sensors in the past 5 years are systematically classified and described in detail. Researchers can quickly know the development status of optical sensors for detection of PAEs in the past 5 years. This review highlights the strengths of each sensor type while also identifying their application limitations, providing researchers with valuable insights into future directions for optical sensor research. [ABSTRACT FROM AUTHOR]

In industry, the monitoring and diagnosis of production processes are crucial issues in ensuring plant reliability, performance and quality. In particular, food processing operations, such as coffee roasting, are subject to numerous risks of failure that can impact on productivity and the quality of the final product. In this context, the main objective of this study was to develop an innovative method for the diagnosis and prognosis of failures in a coffee roasting process. The proposed method differs from standard approaches by using the particle swarm optimization (PSO) algorithm applied to the analysis of signatures of key process variables. This new approach has improved fault detection, with a recognition rate of over 90% for the main types of fault identified, such as heating problems, air obstructions or leaks. In addition to diagnostics, the method has also demonstrated its effectiveness in prognosticating the state of health of the process, with an average error on the prediction of remaining service life reduced to 15%, compared with 35% for fixed-threshold methods. This work has therefore enabled us to develop an innovative method offering superior performance to standard approaches for the diagnosis and prognosis of failures in the roasting process. [ABSTRACT FROM AUTHOR]

The oxidation of bond coat (BC) and interdiffusion between BC layer and superalloys were two mechanisms that contribute to the degradation of thermal barrier coating system (TBCs). The oxidation and interdiffusion of TBCs on single-crystal superalloys were comparatively studied in this work at 950 °C, 1050 °C and 1100 °C over a duration of 1500 h. The results indicated that the thickness of the thermally grown oxide (TGO) progressively increased with the oxidation time and temperature, following a parabolic law. The discontinuous TGO gradually developed into a double-layer structure: the upper layer was a mixed oxide layer, while the lower layer predominantly comprises an Al2O3 layer. Moreover, an interdiffusion zone (IDZ) is formed at the interface between the BC layer and the substrate, with its thickness increasing in response to both temperature and oxidation time. The Cr-rich phases appeared in the IDZ, where Al initially diffused from the BC layer to the substrate, followed by a reverse diffusion process. Simultaneously, Ni and refractory elements diffused from the substrate into IDZ, resulting in the precipitation of the topologically close-packed (TCP) phases and the formation of a secondary reaction zone (SRZ). It has further been shown that Cr-rich phases further diffused into SRZ. Higher oxidation temperatures accelerated the growth of the SRZ and facilitated the transformation of the TCP phases from a blocky to a needle-like morphology. Ultimately, the continuous growth of IDZ and SRZ led to the evolution of the substrate from a monocrystalline to a polycrystalline structure. This study provides valuable data on the microstructural evolution of TBCs and the assessment of their service life. [ABSTRACT FROM AUTHOR]

Highlights Biodegradable biobased polymers are a promising solution to reduce the dependence on conventional plastics and minimize their environmental impact. This work evaluated the recycling capacity of a biodegradable polymer (MaterBi) and its composite with agave fibers. The materials were reprocessed by several cycles using compression molding. Service life simulation was performed using accelerated weathering. Samples from each reprocessing cycle were characterized in terms of melt flow index (MFI), color, porosity, water absorption, compostability, and mechanical and thermal properties. The MFI of MaterBi increased with each cycle, going from 3.5 to 95 g/10 min for the first to sixth cycles and from 2 to 117 g/10 min for the first and fourth cycles for the biocomposite. Reprocessing produced chain scission and modified the thermal and mechanical properties. MaterBi exhibited competitive mechanical properties compared to conventional polymers, even after four reprocessing cycles (tensile, flexural, and impact strengths of 27, 55 MPa, and 30 J/m). Besides potential cost reductions, the agave fiber addition positively affected the tensile and flexural modulus, which remained after the fourth cycle in 1100 and 2300 MPa. The results confirmed that MaterBi and its biocomposites can be recycled for several cycles, extending their useful life before final biodegradation. MaterBi (MB) and its agave fiber biocomposites are suitable for reprocessing. MB tensile and flexural properties remained stable after four reprocessing cycles. Agave fibers make MB more prone to weathering, impacting its properties. MB and its biocomposites degrade in water and compost conditions. [ABSTRACT FROM AUTHOR]

Hydrogels are regarded as ideal tissue scaffold materials owing to their unique advantages, but problems such as low strength and easy cracking have become bottlenecks that limit their practical applicability. Constructing reinforced hydrogels is a widely studied approach for performance enhancement. Therefore, herein, cellulose nanocrystals were introduced as reinforcement into a thermally responsive hydrogel matrix through a Schiff base, achieving a cellulose nanocrystal-reinforced thermally responsive dynamic hydrogel. The CNC-reinforced hydrogel was characterized in detail, and the influence of CNCs on hydrogel properties was systematically investigated. Moreover, the thermally responsive and dynamic properties of the resulting hydrogels were tested to evaluate their mechanical performance. This work provides a feasible solution for the design of hydrogel-based tissue scaffold materials with long service life. [ABSTRACT FROM AUTHOR]

The electrochemical chlorine evolution reaction (CER) is an important electrochemical reaction for industrial applications, but it has serious problems, such as the short service life and low electrolytic efficiency in the extremely dilute chlorine-containing solution. In this paper, a RuO2–TiO2/IrO2–Ta2O5 (RuTi/IrTa) electrode was prepared via a thermal decomposition method involving alternate coating with precursor solutions with two active components, which significantly improved the service lifetime and CER selectivity of electrode materials with low Ir content. The experimental results indicate that the accelerated lifetime (AL) of the RuTi/HC–IrTa electrode with an Ir loading of 374 μg cm−2 can reach 602 h. Although the Ir loading of the HC–IrTa electrode (680 μg cm−2) is about twice that of the RuTi/HC–IrTa electrode, the AL of the HC–IrTa electrode is only 245 h, and the AL of the RuTi electrode (Ru loading: 180 μg cm−2) is only 5 h. If the precursor solutions of HC–IrTa and RuTi electrodes are simply mixed, the AL of the obtained RuTi–HC–IrTa electrode is only 41 h. This suggests that the increase in AL does in fact originate from changing the coating method, rather than simply the use of multiple active components. In addition, the SEM results indicate that the increase of the AL of RuTi/HC–IrTa is due to the change of the corrosion mechanism from pitting corrosion to surface corrosion of active components. Moreover, the CER selectivity of the RuTi/IrTa electrode has also been improved. This may be due to the change in the electronic structure, which is demonstrated through XPS characterization. The RuTi/IrTa electrode has a high electrolysis efficiency in the electrolysis of low-chlorine-concentration solutions. In the preparation of electrochemical disinfection technologies (EDTs), such as acidic electrolyzed water (AEW), more available chlorine content (ACC) can be obtained. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur batteries, despite being a promising solution for next‐generation secondary batteries, require substantial efforts to overcome the challenges of sluggish sulfur redox kinetics, polysulfides shuttling, and Li metal instability before achieving practical viability. Conventional strategies that utilize metal catalysts or soluble redox mediators (RMs) are limited by either impractical producing processes or unsatisfactory service life. Herein, an electrochemically active organic material, phloroglucinol – 2,6‐diaminoanthraquinone (PG‐DAAQ) is synthesized through a green and facile polymerization process to better resolve these issues. Serving as an RM at the cathode, PG‐DAAQ exhibits enduring redox activity within the sulfur operating potential window, leading to enhanced redox kinetics and sulfur utilization. Remarkably, even without any metal elements, PG‐DAAQ exhibits an excellent affinity to polysulfides, thereby suppressing the shuttling and facilitating the formation of a more favorable solid‐electrolyte interface to stabilize Li deposition at the anode. As a result, Li‐S cells employing PG‐DAAQ show significantly enhanced cycling and rate performances than the control cells. Even with a low electrolyte‐to‐sulfur ratio of 6, pouch cells with PG‐DAAQ deliver a reversible discharge capacity of 821 mA h g−1 after 100 cycles at a C/10 rate. [ABSTRACT FROM AUTHOR]

Metallurgical quality of bearing steel is an important foundation and guarantees for determining the performance, accuracy, service life, and reliability of bearings. Nowadays, advances in refining technology have led to a significant increase in the cleanliness of bearing steel, and the control of large‐size carbides (primary, banded, and network carbides) has become particularly important. In this article, the recent research on large‐size carbides regarding morphology, precipitation mechanism, and control methods is reviewed. Firstly, the morphological characteristics of carbides are summarized. Primary carbides appear as blocky, lamellar, or irregular shapes, while banded carbides are distributed in bands. Network carbides mainly precipitate along the austenitic grain boundaries and aggregate to form networks. Secondly, the precipitation mechanisms of carbides are summarized. Dendritic segregation is the fundamental cause of the formation of primary and banded carbides, whereas network carbides are the supersaturation precipitation of carbon at austenite grain boundaries. Finally, methods for controlling large‐size carbides are summarized, including improving dendritic segregation, high‐temperature diffusion annealing, improving rolling and cooling processes and using magnesium or rare‐earth treatments. No single method offers sufficient carbide control, and mechanism of rare‐earth refining carbides is unknown. Thus, a comprehensive approach should be used in production to effectively regulate carbides in steel. [ABSTRACT FROM AUTHOR]

For producing high‐capacity silicon (Si) anodes, a combined gas‐phase deposition and etching technique is developed to construct yolk‐shell structured silicon‐carbon composites. As a novel etching agent in battery field, NF3 is applied to selectively etch Si to tailor the architecture. Si particles as self‐sacrificed precursor have no need to build artificial or complex templates in advance, thereby greatly simplifying fabrication process and showcasing practicality. As a result, yolk‐shell structured silicon‐carbon composites are successfully fabricated in a single step. Sufficient buffer space between Si and carbon layer accommodates the significant expansion of Si during lithiation, preventing fracture of the carbon layer, which greatly improves service life of Si‐based anodes. Moreover, the refined particle size of Si and abundant pores in inner Si cores enhance the lithiation and de‐lithiation kinetic. Even with a high Si loading of 3.9 mg cm−2, the produced anode exhibits a superior areal capacity of 16.3 mAh cm−2 at 0.2 mA cm−2. Furthermore, at a high current density of 4 A g−1, it demonstrates an excellent capacity of 1114 mAh g−1 after 1000 cycles with a capacity retention of 96.3%. Additionally, with pre‐lithiation, it is successfully paired with an iron trifluoride cathode to construct high‐energy lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Alumina-spinel and alumina-magnesia castables are important for steel ladle applications primarily for the bottom and side wall areas respectively. Presence of spinel in alumina castables enhances the resistances against corrosion and thermal shock and improves the performance and service life of the steel ladles. Development of these type of castables is planned in the present study in presence of Cr 2 O 3 as an additive using high alumina cement as binder. Variation in spinel (10 and 20 wt%) and MgO (2.8 and 5.6 wt%) content was also explored, along with two different particle size distributions (q value 0.21 and 0.29) for different flow consistencies. The castable compositions were processed conventionally and evaluated for various refractory properties after heat treatments at 110, 1000 and 1550 °C. Both the castables showed well developed refractory properties with alumina-magnesia castable having better slag resistance due to greater extent of calcium hexa aluminate phase formation protecting the refractory. [ABSTRACT FROM AUTHOR]

In order to reduce the vibration localization of multistage blade-disk system of aeroengine compressor, the integral model and substructure model of multistage blade-disk system are established by using substructure modal synthesis method, and the dynamic characteristics of two models are analyzed and the accuracy of the substructure model is verified by comparison. Based on the substructure model, two optimization algorithms of the random wear mass and the snake optimization are proposed. The results show that the vibration amplitudes of the two models are in good agreement in the first 200 modes, and the substructure model meets the requirement of analysis accuracy. Both optimization algorithms can effectively reduce the degree of the vibration localization of the mistuned blade-disk system. The random wear mass algorithm can quickly reduce the amplitude of the blade. The snake optimization algorithm can find the global optimal solution with enough iterations. The results show that the maximum vibration amplitude and the vibration localization factor after optimization are reduced by 5.72 % and 12.0 % respectively by using the random wear mass algorithm, and that of 9.13 % and 16.7 % respectively by using the snake optimization algorithm. The analysis method presented in this paper takes into account the analysis efficiency and analysis precision, it can be used for dynamic analysis and vibration reduction optimization of large power machinery such as aeroengine and gas turbine, and provides a basis for further improving the reliability and service life of aircraft. [ABSTRACT FROM AUTHOR]

The ultrasonic surface rolling process (USRP) can effectively reduce surface roughness, reduce the stress concentration and extend the service life of a workpiece. Surface roughness prediction by finite element simulation has been a hot research topic of late. Most of the previous studies are based on plane models, but the influence of initial surface roughness on the prediction results of shaft parts has not been considered. In this paper, wavelet transform is used to reconstruct the measured cylindrical sample surface data, and the shaft model with initial surface roughness is established. Then the finite element simulation model of USRP is established to predict the surface roughness. The results show that compared with the experimental results, the maximum error of the proposed method is 9 %, which is better than that of the finite element simulation model without considering the initial surface roughness, which verifies the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This paper proposes a design and analysis method for automatic production lines. Through analyzing the manual assembly process of battery cells and reed pipes, an automatic assembly line is designed. Based on Visual Components, a virtual assembly system of the production line is established, which simulates the actual working process, solves the bottleneck problems, and obtains a set of optimal working parameters of the assembly line. Through the optimization analysis of production line efficiency, it is concluded that the working speed of the reed pipe robot is the critical factor affecting production efficiency. The modified D-H parameter method is used to establish the kinematic model of the reed pipe robot, and polynomial interpolation planning is carried out for the critical trajectory points, which optimizes the motion trajectory of the reed pipe robot and improves the service life. [ABSTRACT FROM AUTHOR]

This paper utilizes the Wohler curve and the J-integral principle to predict the service life of purposely-damaged acrylonitrile butadiene styrene (ABS) specimens. The hardness of single- and double-notched specimens was measured using the J-integral, facilitating a comparison between two different types of defects. By analyzing the Wohler curve, we were able to examine the decline in the service life of the ABS specimens over various time intervals. According to the comparison, a hole with a single internal notch flaw is not as detrimental as one with two notch defects. [ABSTRACT FROM AUTHOR]

Sintering is a common phenomenon, which often takes place during the oxidation roasting process of molybdenite concentrate in multiple-hearth furnaces. The occurrence of sintering phenomena has detrimental effects on the product quality and the service life of the furnace. In this work, the influence of two key factors (roasting temperature and K content) on the sintering behavior is investigated using molybdenite concentrate as the raw material. Different technologies such as XRD, FESEM-EDS, and phase diagrams are adopted to analyze the experimental data. The results show that the higher the roasting temperature is, the greater the mass loss and the more serious the sintering degree will be. The results also show that with the increase in K content, the mass loss of the raw material is first increased and then decreased, while its sintering degree is still gradually increased. The sintering products obtained during the oxidation roasting process are often tightly combined with the bottom of the used crucible with a smooth and dense surface structure, while their internal microstructures are very complicated, which not only includes numerous MoO3 species, but also unoxidized MoS2, Mo sub-oxide, SiO2, and a variety of molybdates. Among them, both MoO3 and molybdates can be easily dissolved into the ammonia solution, leading to a residue mainly composed of SiO2 and CaMoO4. This study also finds that the sintering phenomenon is caused by the increase in local temperature and the formation of various low-melting-point eutectics. It is suggested that decreasing the roasting temperature and K content, especially the K content, are effective methods for reducing the sintering degree of molybdenite concentrate during the oxidation roasting process. [ABSTRACT FROM AUTHOR]

The conventional method for detecting road defects relies heavily on manual inspections, which are often inefficient and struggle with precise defect localization. This paper introduces a novel approach for identifying and locating road defects based on an enhanced ML-YOLO algorithm. By refining the YOLOv8 object detection framework, we optimize both the traditional convolutional layers and the spatial pyramid pooling network. Additionally, we incorporate the Convolutional Block Attention to effectively capture channel and spatial features, along with the Selective Kernel Networks that dynamically adapt to feature extraction across varying scales. An optimized target localization algorithm is proposed to achieve high-precision identification and accurate positioning of road defects. Experimental results indicate that the detection accuracy of the improved ML-YOLO algorithm reaches 0.841, with a recall rate of 0.745 and an average precision of 0.817. Compared to the baseline YOLOv8 model, there is an increase in accuracy by 0.13, a rise in recall rate by 0.117, and an enhancement in average precision by 0.116. After the high detection accuracy of road defects was confirmed, generalization experiments were carried out on the improved ML-YOLO model in the public data set. The experimental results showed that compared with the original YOLOv8n, the average precision and recall rate of all types of ML-YOLO increased by 0.075, 0.121, and 0.035 respectively, indicating robust generalization capabilities. When applied to real-time road monitoring scenarios, this algorithm facilitates precise detection and localization of defects while significantly mitigating traffic accident risks and extending roadway service life. A high detection accuracy of road defects was achieved. [ABSTRACT FROM AUTHOR]

The fiber-reinforced polymers (FRP) bar is a promising solution to problems caused by steel rebar corrosion in concrete. To assess the service life of the FRP bar based on accelerated test results, it is crucial to have a reliable model. Here, a modified exponential (MEP) model is proposed based on the Avrami equation. The Avrami equation provides a theoretical foundation for the empirical exponential (EP) model and does not a priori fix the power of the exposure time to one. A database containing 903 data points from 74 groups of test specimens is assembled to compare the reliability of the MEP model vis-a-vis the EP, single logarithmic, double logarithmic, and power function models. The combination of Root Mean Square Error (RMSE), the Mean Absolute Error (MAE), and the coefficient of determination (R2) criteria is proposed for assessing model reliability. It is shown that in certain cases the combined criteria, versus R2 alone, significantly increase the number of test groups meeting the acceptable performance limit. Observed test data aberrations are found to have minor influence on the results of the EP model, but they significantly influence the results of the other four models. The EP model generally predicts the lowest activation energy and the smallest strength retention for similar groups of bars, while the predicted values of the other four models exhibit a relatively small difference. The difference between the predicted strength retention values of the EP and MEP models shows an increasing trend with the increase of the absolute value of (1 − n), where n is the power of the exposure time in the MEP model. [ABSTRACT FROM AUTHOR]

The behavior of airport precast concrete pavement (APCP) involving new design and construction concepts was experimentally analyzed under environmental and moving airplane loads, and the long-term performance of the APCP was evaluated using fatigue failure analysis. The strain characteristics and curling behavior of the APCP under environmental loads were comprehensively analyzed. The APCP slabs exhibited a pronounced curling phenomenon similar to conventional concrete pavement slabs. The dynamic response of the APCP subjected to impact loads was analyzed by performing heavy weight deflectometer tests. The test results confirmed that the vertical deformation of the APCP was small and within the typical range of vertical deformation of conventional concrete pavement. The dynamic strain response of the APCP under moving airplane loads was then analyzed and the strain variation during day and night times was compared. The strains during the day were found to be significantly larger than those at night under airplane loads because of the curling phenomenon of the APCP slabs. Finally, the long-term performance of the APCP was evaluated using fatigue failure analysis based on the obtained behavior. Even using the most conservative fatigue failure prediction model, the service life of the APCP was ascertained to be more than 30 years. Based on the overall results of this study, it is concluded that the APCP, which is designed to reduce slab thickness by placing reinforcing bars in the slabs via reinforced concrete structural design, exhibits typical behavior of concrete pavements and can be successfully applied to airport pavement rehabilitation. [ABSTRACT FROM AUTHOR]

Reciprocating pumps are widely used in the current oil extraction process, and the plunger is a vulnerable part of these pumps that directly determines the service life of the reciprocating pump. To improve the service life of plungers, Ni60/WC coatings were applied to the surface of 45-steel plungers via laser cladding technology to improve wear and corrosion resistance. Defect-free and dense Ni60/WC coatings were successfully applied to the plunger surface with strong metallurgical bonding between the coating and the substrate. The coating consists mainly of a γ-(Ni, Fe) phase, which contains isotropic and isotropic-like crystals, dendritic crystals, and columnar crystals in the top, middle, and bottom regions of the coating, respectively. The service performance of the laser cladding coating was compared to the flame-sprayed plunger, which is widely used, and the laser cladding coating has a microhardness of up to 821.8 HV0.5, which is higher than that of the flame-sprayed coating (545.5 HV0.5) and the 45-steel substrate (200 HV0.5). The laser cladding coating has a lower friction coefficient and a smaller volumetric wear rate, and the corrosion current density and corrosion rate in the NaCl solution are 2.52 × 10−7 A/cm2 and 2.96 × 10−3 mmPY, respectively, which indicates superior corrosion resistance to the flame-sprayed coating and the substrate. The laser cladding of reciprocating pump plunger surfaces has a significantly improved comprehensive performance and is a promising way to increase the service life of reciprocating pumps. [ABSTRACT FROM AUTHOR]

From demolition to replacement, the Hahnwald bridge in Niedernhausen The new replacement construction in the route of the L 3027 is a road bridge over eleven railway tracks in the city centre of Niedernhausen with a span of 73 m. The planning was carried out under great time pressure, because the existing bridge had to be decommissioned before its remaining service life due to a pier misalignment and a replacement was urgently needed for traffic reasons. Due to the changes in design demanded by the safety requirements of the Deutsche Bahn (DB), the bridge was designed as a tied‐arch bridge (with an overhead supporting structure). In addition to the adaptation of the structure to the state‐of‐the‐art, a cycle lane was added to the road cross‐section. The superstructure was produced from single elements carried to an assembly site about 600 m above the village of Niedernhausen. In early 2023 took place the transport of the about 600 t of the heavy steel construction through the village of Niedernhausen and finally the launching to its final position with the help of an intermediate support. The time‐period between the demolition and launching of the new tie‐arch bridge lasted from September 2021 to June 2023. This report covers the period from the challenges posed to maintenance management of the existing bridge to the planning of the new replacement structure, construction and opening to traffic. [ABSTRACT FROM AUTHOR]

Cemented pavement materials (CPMs) are essential components in pavement structures, yet accurately predicting their service life due to fatigue damage remains challenging. Laboratory fatigue test results are commonly employed to predict the service life of CPMs by applying a lab-to-field shift factor (SF). However, traditional approaches rely heavily on experimental data, posing challenges in ensuring the certainty of lab-to-field results. Additionally, inconsistencies in lab-to-field fatigue failure criteria further complicate SF development. To address these challenges, this study proposes a mechanism-based methodology for developing SF. This methodology comprises a rigorous two-scale fatigue model developed by the authors to characterise the fatigue performance of CPMs at the lab scale and predict their performance at the field scale, thereby facilitating the development of SFs. These SFs are established based on a consistent lab-to-field fatigue failure criterion (i.e. the modulus reduction of CPMs). By accounting for strain differences between laboratory and field scales, SFs are derived in the strain-fatigue life space. Application of this approach to typical Australian CPMs, namely siltstone and hornfels, yields mechanism-based SFs of 1.19 and 1.21, respectively. [ABSTRACT FROM AUTHOR]

Lead halide perovskite exhibits great prospects in next‐generation display. However, single‐cation inorganic perovskite nanocrystals (NCs) still suffer from offset gamut coordinates determined by bandgap, short operating life, and low‐efficiency in light‐emitting diodes (LEDs), on account of the limitations in lattice stability and defect levels. Here, a thermodynamic co‐competition strategy is proposed for fabricating Cs1−xFAxPbBr3 NCs, which reveals the spatial distribution of A‐site cations and the improvement of photoelectronic performance. This strategy achieves precise control of NCs in the pure‐green range with an accuracy of sub‐nanometer, further promotes the comprehensively filling‐suppressing effect of incongruous lattice and surface defects. Finally, the high‐precision adjusting in electroluminescence is achieved, and the champion device achieves a CIE coordinate of (0.121, 0.788), meeting the pure‐green range in BT.2020. Simultaneously, the PeLED demonstrates an EQE exceeding 20% with superior stability, accompanied by 20‐fold improvement in lifetime, indicating tremendous potential in next‐generation display. [ABSTRACT FROM AUTHOR]

Purpose: Organic coatings are widely used for protecting metal equipment and structures from corrosion. Accurate detection and evaluation of the protective performance and service life of coatings are of great importance. This paper aims to review the research progress on performance evaluation and lifetime prediction of organic coatings. Design/methodology/approach: First, the failure forms and aging testing methods of organic coatings are briefly introduced. Then, the technical status and the progress in the detection and evaluation of coating protective performance and the prediction of service life are mainly reviewed. Findings: There are some key challenges and difficulties in this field, which are described in the end. Originality/value: The progress is summarized from a variety of technical perspectives. Performance evaluation and lifetime prediction include both single-parameter and multi-parameter methods. [ABSTRACT FROM AUTHOR]

In this article, power quality disturbances, such as voltage and current unbalances, series and shunt faults, are monitored in three-phase synchronous machines. Because the imbalances affect machine efficiency and service life, it is essential to figure out whether the three-phase voltages/currents are balanced or unbalanced. An integrated detection algorithm is proposed to detect the unbalanced voltages/currents and various abnormal conditions precisely and quickly, which is based on the coherence estimator. Most existing detection methods require more than one cycle time to determine the contingency conditions, while the proposed technique detects these situations in a fast and discrete protection system. The suggested scheme acquires instantaneous measurements of the three-phase voltages and currents taken at the synchronous machine terminals in order to calculate fifteen coherence coefficients that are utilized to detect and assess any unbalance or trouble accurately and swiftly. A new proposal for imbalance and disturbance indicators based on the coherence estimators is developed in this study. Multiple test cases have been conducted to validate the proposed algorithm capabilities using a real power system, which includes a motor-generator set, a three-phase load and measurement transformers. The experimental results have been revealed that the relay reliability and accuracy percentages have been found to be 98.28% and 98.52%, respectively. The quantitative findings of the imbalance and disturbance assessment are recorded. [ABSTRACT FROM AUTHOR]

With the advancement of modern construction technology, reinforced concrete (RC) has become the most widely used composite construction material. Corrosion of embedded reinforcement bars in RC structures, which is essentially the result of carbonation and chloride attack, is regarded as one of the weaknesses. Hence, many research studies have been conducted to evaluate the effect of corrosion on the service life of RC structures. However, so far no proper equation has been derived to predict the extent of carbonation-induced corrosion. Identifying this research gap, the present study intends to derive an equation for the coefficient of carbonation (K), which is the governing measure of the rate of carbonation. This paper identifies concrete grade, exposed CO2 gas concentration, and exposed Relative Humidity (RH) level as the major parameters affecting the carbonation process. The behaviour of each factor along with K was identified by conducting a modified accelerated carbonation test (ACT). These experimentally derived K values were statistically analysed under the principle of multiple linear regression, to derive an equation for predicting K values for RC structures. Based on the results, this paper proposes two user-friendly mathematical models covering the entire environmental RH range to predict the K values of RC structures. [ABSTRACT FROM AUTHOR]

Pipeline structures usually suffer from serious vibration problems due to pressure pulsation and fluid excitation, potentially compromising their structural stability and service life. In this paper, a lightweight body center cubic (BCC) meta-lattice sandwich sleeve is proposed to isolate vibrations in pipelines within a broadband frequency range. The vibration isolation is based on the concepts of the locally resonant metamaterials. An equivalent mass-spring model is conducted to theoretically predict frequency range and elucidate the generation mechanism of the band gap. In addition, an analytical methodology is also proposed to predict the equivalent stiffness of the BCC meta-lattice sleeves. The influence of geometric parameters and configuration layout of the meta-lattice on the flexural wave band gap is further investigated. Numerical studies and experimental tests are also conducted to validate the vibration isolation effectiveness, considering various pipe lengths and different numbers of meta-lattice units. The proposed design provides fundamental support for the design of lightweight vibration isolation structure for pipelines. [ABSTRACT FROM AUTHOR]

Porous mullite ceramics have good properties for high‐temperature applications, but porosity gives place to ceramics with low mechanical strength, which restricts the service life in their potential applications. Therefore, performing modifications at the microscale to increase the mechanical strength has become a current challenge to expand its application fields. This work describes the properties of a porous mullite–zirconia composite produced by ceramic processing, using industrial kaolin and stabilized zirconia as raw materials. The growth of mullite needle‐like grains to reinforce the ceramic was promoted by the addition of a molybdenum oxide precursor. The effect of zirconia on the composite was analyzed through an experimental multi‐technique approach and considering a pure mullite sample, identically processed, as a reference. The novel composite has a porosity of about 50%, and presents a homogeneous microstructure, with interlocked mullite needle‐like grains and dispersed rounded zirconia grains. This morphology restricts the mullite tendency to shrink during sintering, giving the material a higher stiffness. In particular, the presence of zirconia in the composite improves both the flexural strength and the apparent Young modulus of the material (about 20% and up to 600%, respectively). These results encourage further investigations to establish this composite for different technological applications. [ABSTRACT FROM AUTHOR]

The prediction of the time-dependent behavior of high-performance concrete (HPC) structures is essential to evaluating their service life. This prediction relies on the shrinkage and creep properties of HPC. However, unlike conventional concrete, the binary and ternary composite system of supplementary cementitious materials (SCMs) in HPC has demonstrated different shrinkage and creep properties. This difference makes it challenging to accurately predict these properties using existing material models in code and standard practices, i.e., ACI, fib, B4, and GL. These models exhibit significant deviations in prediction under standard statistical evaluation methods due to the influence of SCMs. To overcome this challenge, intelligent artificial neural network (ANN) models have been developed using a feed-forward backpropagation training algorithm. The ANN models consider a widely compiled indigenous database of shrinkage and creep and consist of the most realistic experimental relationship with the effecting extrinsic and intrinsic key parameters. These parameters include standard concrete mix design material proportions, mechanical and physical properties, environmental conditions, and aging factors to obtain shrinkage and creep properties of HPC. All concrete material properties influencing the behavior of shrinkage and creep have been related based on experimentally measured results and incorporated as input parameters in both intelligent developed ANN models. The accuracy of prediction of both ANN models has been substantiated by the experimentally measured database and existing material models as comparative appraisals using several statistical metrics. The developed ANN models to predict such complex nonlinear properties of HPC are more practical and beneficial than existing material models, which will help to fulfill sustainable development and improve the service life of HPC structures. [ABSTRACT FROM AUTHOR]

Bristles in the first few rows float up from the rotor surface due to the radial airflow in the gap between the front plate and bristle pack, which directly affects seal performance and the service life of a brush seal. In this paper, firstly, two three-dimensional transient calculation models for a traditional brush seal (TBS) and a brush seal with disturbance-suppressing holes (DSBS) are established, respectively, based on the arbitrary Lagrange–Eulerian (ALE) method to study bristle deformation characteristics and leakage flow characteristics of the seals. Furthermore, effects of disturbance-suppressing (DS) hole structural parameters (i.e., height, diameter, and number of hole rows) were investigated to reveal the suppression mechanism of the DS holes on the buoyancy effect of bristles. The results showed that as soon as free ends of bristles at the first few rows moved along direction of the front plate in response to the radial airflow from the gap between front plate and bristle pack, a buoyancy effect of bristles occurred. The DSBS with DS holes set in the front plate of the TBS had a lower deformation of the bristles and a lower leakage amount of seal compared with that of TBS, indicating a good suppression to the buoyancy effect. With decreasing hole height and increasing hole diameter and number of hole rows, the suppression of bristle disturbance gradually increased due to decreases of the radial airflow and increases of torque acting on the bristles. [ABSTRACT FROM AUTHOR]

Aging infrastructure is a significant concern to many system operators who might struggle to operate, maintain, and improve systems and infrastructure assets due to spatially buried assets over a large area, uncertainty about their condition, and lack of a comprehensive planning. These challenges often lead to a reactive approach to maintenance, causing emergency situations due to unexpected asset failures. This study proposes a suite of risk-based asset management plan tools to extend the service life of a drainage pipe network with a length of 580 km managed by a city council in Australia. The proposed management plan tools are based on a reactive–proactive approach to manage risk in which proactive condition monitoring is applied to critical and important pipes for detecting failure conditions in a timely manner. A sample of critical closed-circuit television (CCTV) inspected pipes selected from pipe network is used to predict the current and future condition of the pipe network using a Markov deterioration model. The predicted condition is used to support various implementation tasks of an asset management plan and accounting requirements. The key findings of the case study include a calibrated Markov deterioration curve showing slow rate of deterioration for a drainage network, average service life estimation (120–180 years) for drainage pipes, lowest-cost inspection interval determination (i.e., 7–14 years) for detecting poor condition, and estimated annual inspection and replacement cost for a drainage network. Practical Applications: A significant number of local governments and city councils around the world manage drainage pipe networks as high capital asset value. Extending the service life of drainage pipes with reduced life-cycle cost and managed failure risk is a challenge and an essential task for asset management. This study introduces a proactive–reactive asset management strategy and a suite of decision support tools to assist in achieving such challenging tasks. For example, instead of using the common design service life of 80–100 years for asset renewal planning, this study demonstrates, through a case study, that service life can be extended to 120–180 years, resulting in significant savings of capital investment. To control failure risk and reduce life-cycle cost during the extended service life, a suite of decision support models including an optimal inspection model, a failure risk model, and others can be used to justify annual maintenance funding, timely detecting poor condition, and suggesting appropriate maintenance and rehabilitation planning. The results show that the inspection interval can be 7–14 years, and the Markov deterioration model predicted that the current network has 7% of pipe in a failure condition, which will increase by 1.67% over the next 10 years, which can justify renewal funding. [ABSTRACT FROM AUTHOR]

Corrosion in reinforced concrete structures is among the major degradation mechanisms. The quantification and description of the spatial distribution of the corrosion condition within a structure on the basis of condition assessments are important. This study considered half-cell potential mapping data as a widely used technique to detect corrosion in reinforced concrete structures. A four-step workflow was proposed to analyse half-cell potential data with geostatistical techniques, first consisting of trend identification and possible trend removal. The obtained residuals were then subjected to a quantile-quantile transformation. Subsequently, experimental variograms were calculated and fitted with variogram models to estimate the correlation lengths. A case study with data from a road tunnel confirms the applicability of the workflow. It was assumed that the identified trend is primarily a result of the heterogeneity of the exposure conditions within the structure that ranges several metres. The residuals are interpreted as the result of the heterogeneities of material resistances that give rise to spatial variability in corrosion probability on a shorter distance range. The proposed analysis may be utilised for service life modelling (e.g. based on random fields), planning maintenance works, or optimising the grid size for half-cell potential measurements. [ABSTRACT FROM AUTHOR]

During actual operation, a steel wire rope is deformed due to stress interaction between its internal steel wires. In this article a finite element approach is employed to simulate the interaction of steel wire under practical working conditions. In addition, according to the amount of fatigue broken wire under experimental conditions, corresponding parameters are put forward to estimate the service life of steel rope. In this article, the effect of various conditions on service life of steel wire rope is analyzed, and approaches are put forward to improve its service life. The results show that the total stress in straight strand is larger than side strand stress, while the stress increases from inside to outside while increasing from inside to outside. The bigger the pulley diameter, the more steel wire breaks inside the wire rope. [ABSTRACT FROM AUTHOR]

• A novel model for investigating the vehicle-induced fatigue damage of fastener clips in high-speed railway is established. • An efficient dynamic solution and an iterative method are introduced into the vehicle-track (VT) dynamic interaction. • The spatial variability of the fastener is characterized in the VT system by combining the random field expansion method. • The stochastic fatigue damage evolution of the fastener clips and its impact on the VT system have been revealed. To investigate the vehicle-induced fatigue damage evolution of fastener clips and their impact on the vehicle-track (VT) system, a numerical dynamic model is established to achieve probabilistic evaluation. The "rain flow" counting method is adopted to describe the stress cycles of the hazard area of the clips, and the S-N curve is used to predict the fatigue life of the clips. The solution of the dynamic equation of motion is obtained by the time-domain Green's function method, which is an effective method to improve computational efficiency. A versatile iterative algorithm is adopted to solve the nonlinear system considering the damaged clips. In the probabilistic evaluation framework, a novel random field method is employed to depict the spatial variability of clips' strength. The applicability of the model established in this work in aspects of expressing random damage of fasteners and evaluating the dynamic behavior of the system is demonstrated by different numerical examples. The results show that the dynamic responses of the train and track system significantly exacerbate as the number of train cycles increases, which is closely related to the variability and non-uniform damage of the fasteners. The probability of cumulative damage to the fasteners induced by the train follows a three-stage rule, and the fatigue damage of the non-uniform fastener system caused by the train is greater than that of the uniform situation. In addition, the short wave components of track irregularity will significantly exacerbate the damage to fasteners and therefore degrade the status of the railway line. As the driving speed increases, the damage to the fasteners also increases, but the impact of vehicle speed on the fastener damage is smaller than that of track irregularity, especially in the range of fatigue damage greater than 0.9. Therefore, maintaining the geometric smoothness of the track, controlling the uniformity of the mechanical properties of the fasteners, and reducing the driving speed are feasible measures to extend the service life of the fastener system, thereby ensuring the operation of high-speed trains. [ABSTRACT FROM AUTHOR]

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Polyethylene (PE) pipes are widely used in urban gas transportation due to their good toughness and corrosion resistance. Currently, the designed service life of a PE pipeline is 50 years, and some urban gas PE pipelines are approaching their service life. However, research on the aging assessment of PE pipelines is not complete, and it is impossible to effectively predict their aging status in service. Once urban gas PE pipelines are damaged, serious accidents may be caused. PE80 and PE100 pipelines are commonly used for urban gas, and improved accelerated aging tests were conducted considering different conditions of pressure, pipe diameter, and temperature. According to the experimental results, an aging life prediction method for PE pipes was constructed based on the Arrhenius formula considering multiple effect factors. [ABSTRACT FROM AUTHOR]