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Several research studies have investigated the degradation of BaTiO3-based dielectric capacitor materials, focusing on the impact of composition, defect chemistry, and microstructural design to limit the electromigration of oxygen vacancies under electric fields at finite temperatures. Electromigration can be a dominant mechanism that controls failure rates in the individual multilayer ceramic capacitor (MLCC) components in testing the reliability of failures with highly accelerated lifetime testing (HALT) to determine the mean time to failure of MLCCs surface mounted onto printed circuit boards (PCBs). Conventional assumptions often consider these failures as independent, with no interaction between components on the PCB. However, this study employs a Physics of Failure (PoF) approach to closely examine transient degradation and its impact on MLCC reliability, emphasizing thermal crosstalk and its influence on dependent and independent failure rates. Finite element analysis thermal modeling and infrared thermography were used to assess the impact of circuit layout and component spacing on heat dissipation and thermal crosstalk under various electrical stress conditions. The study distinguishes between dependent and independent failures under a HALT, quantified through a β′ factor reflecting common cause failures due to thermal crosstalk. Through a series of experimental and statistical analyses, the β′ factor is evaluated with respect to temperature, voltage, and component spacing. These insights highlight the importance of understanding the nature of the data in reliability testing of MLCCs and optimizing the layout design of high-density circuits to mitigate dependent failures, improving overall reliability and informing better design and packaging strategies. [ABSTRACT FROM AUTHOR]

The degree of microstructural non-uniformity and the lifetime extension of multilayer ceramic capacitors (MLCCs) were evaluated by repeating the fabrication of "prebreakdown" MLCCs through highly accelerated life tests (HALTs), the removal of the insulation resistance-degraded layer, and the reformation of the terminal electrode. The total mean time to failure (MTTF) tended to extend and converge as HALTs were repeated. Microstructural analysis in the degraded local area revealed a clear correlation between the shorter lifetime and the minimum number of grains per unit dielectric layer. After HALTs were repeated, the number of grains came close to and converged as much as undegraded areas over a longer lifetime. These results imply that degradation occurs in order from the greatest degree of microstructural non-uniformity and that the weakest-link model can be understood by treating the lifetime as MTTF. [ABSTRACT FROM AUTHOR]

C4F7N [2,3,3,3-tetrafluoro-2-(trifluoromethyl)propanenitrile]/CO2 gas mixtures are being developed as an eco-friendly electrical insulator to replace SF6, the most potent greenhouse industrial gaseous dielectric. However, recent studies have reported complicated and often conflicting decomposition pathways for C4F7N/CO2 gas mixtures, which has raised concerns. In this work, the decomposition characteristics of C4F7N/CO2 gas mixtures were studied comprehensively by both designed computations and experiments. Computations were performed starting from fundamental propositions of C4F7N/CO2 decompositions, which were further experimentally verified by pyrolysis, long-term thermal aging with/without catalytic materials (industrial-grade molecular sieves 4A), and electrical decomposition by spark discharge. The results of both computations and experiments suggest that in an ideal thermal decomposition, C4F7N is likely to decompose into C2F6 and small fluoronitriles first at high temperatures. The generation of C3F6 and C2N2 from C4F7N thermal decomposition at lower temperatures appears because of the catalytic effect of incompatible materials, for example, the industrial-grade molecular sieves 4A that we tested. The electron impact dissociation of C4F7N plays an important role in C4F7N electrical decomposition, leading to additional formation of distinctive small molecules of CF4 and C2N2 of low concentrations. It was pointed out based on a real arcing test in a load disconnector that the decomposition of C4F7N gas mixtures in real applications will be at a much moderate and manageable rate than what was obtained from the highly accelerated laboratory tests presented in this work. The signatures of decomposition products extracted in this study provide invaluable guidance for developing decomposition-based diagnosis and fixation of decomposition byproducts toward SF6-free power grids. [ABSTRACT FROM AUTHOR]

Circular steel-tube members are extensively used in various large-scale steel structures. The detrimental effects of corrosion on the ultimate bearing capacities of these structures require urgent attention. This study designed six circular steel tube specimens to explore the degradation pattern of the ultimate bearing capacity of corroded circular steel tubes under axial compression; three were subjected to accelerated corrosion by electrification, and the other three were used as the control group. Following the accelerated corrosion test, both groups of specimens were subjected to material-property and axial-compression tests. These tests provided data on the bearing capacity and midspan displacement of the corroded circular steel tubes, allowing for the construction of load–displacement relationship curves. The test results demonstrate that corrosion significantly affects the bearing capacity of circular steel tubes. As the severity of the corrosion increased, the bearing capacity and stiffness of the corroded circular steel tubes progressively weakened. To simulate the behavior of circular steel tubes, a numerical model was established that provided the ultimate bearing capacity under axial compression and generated load–displacement curves. The simulation results closely aligned with the test results. This study introduced a novel approach for accurately computing the stability-bearing capacity of circular steel tubes subjected to corrosion and axial compression. Comparative analyzes with test results validated the superior performance of the proposed method in accurately predicting the ultimate bearing capacity. [ABSTRACT FROM AUTHOR]

The use of accelerated bridge construction methods such as prefabricated bridge elements, lateral slide, and self-propelled modular transporter has increased in recent years to minimize on-site construction time and related traffic disruptions, and to improve safety, quality, and sustainability. This paper presents the development and evaluation of six novel machine-learning models for estimating the cost of conventional and accelerated bridge construction methods during the early design phase. The models were developed in four phases that focused on (1) collecting a data set of 413 conventional and accelerated bridge projects; (2) preprocessing the collected data to ensure its quality and reliability by identifying predicted and predictor variables, classifying predictor variables, cleaning data, transforming predictor variables, and splitting data into training and testing data sets; (3) training the models using ordinary least squares, least absolute shrinkage and selection operator (LASSO) regression, ridge regression, random forest, gradient boosting, and extreme gradient boosting; and (4) evaluating and validating the performance of the developed models. The outcome of the validation phase showed that the extreme gradient boosting model outperformed the other machine-learning models in terms of the metrics mean absolute percentage error, mean absolute error, and median absolute error; and the gradient boosting model outperformed the other models in the metric root mean square error. The developed machine-learning models and their improved cost estimating accuracy are expected to provide much-needed support to bridge planners and enable them to accurately estimate, compare, and select the most cost-effective construction method for their planned bridge construction projects during the early design phase. [ABSTRACT FROM AUTHOR]

The remaining useful life prediction of rolling bearing is vital in safety and reliability guarantee. In engineering scenarios, only a small amount of bearing performance degradation data can be obtained through accelerated life testing. In the absence of lifetime data, the hidden long-term correlation between performance degradation data is challenging to mine effectively, which is the main factor that restricts the prediction precision and engineering application of the residual life prediction method. To address this problem, a novel method based on the multi-layer perception neural network and bidirectional long short-term memory network is proposed. Firstly, a nonlinear health indicator (HI) calculation method based on kernel principal component analysis (KPCA) and exponential weighted moving average (EWMA) is designed. Then, using the raw vibration data and HI, a multi-layer perceptron (MLP) neural network is trained to further calculate the HI of the online bearing in real time. Furthermore, The bidirectional long short-term memory model (BiLSTM) optimized by particle swarm optimization (PSO) is used to mine the time series features of HI and predict the remaining service life. Performance verification experiments and comparative experiments are carried out on the XJTU-SY bearing open dataset. The research results indicate that this method has an excellent ability to predict future HI and remaining life. [ABSTRACT FROM AUTHOR]

AbstractIn many reliability applications, degradation of products has to be measured destructively, and destructive degradation tests are a useful tool to evaluate product reliability. Previous studies commonly obtain an optimal degradation test plan numerically with given planning values of model parameters, under a default assumption that stress acceleration is necessary. In this study, we use the general path model for product degradation and derive closed-form solutions for optimal designs of a destructive degradation test, under the planning objective of minimizing the asymptotic variance of the estimated lifetime quantile. Based on these results, we further identify conditions under which acceleration is necessary or unnecessary. It is found that the key parameters that determine the necessity of acceleration are the lifetime quantile and the parameter associated with the accelerating variable in the link function. We demonstrate the application of the results by applying them to an adhesive bond test and a seal test. Several compromise plans are investigated to robustify the test. Supplementary materials for this article are available online. [ABSTRACT FROM AUTHOR]

The automatic ventilation door in mining operations is a crucial component for ensuring production safety and maintaining ventilation system stability. However, the primary power element of this equipment—the cylinder—often lacks effective monitoring, which can compromise operational reliability. To address this gap, this study proposes a Weibull life prediction method, integrating Bayesian inference and Monte Carlo simulation, aiming at anticipating changes in cylinder reliability. This proactive approach supports timely maintenance to prevent. Given the unknown shape and scale parameters of the Weibull distribution, Bayesian methodology is applied, alongside accelerated life testing principles, to analyze the life characteristics of cylinder. By deriving the posterior distribution function of Weibull parameters, Monte Carlo simulation is employed to estimate these parameters across various operational conditions. This method reveals how life characteristics relate to environmental factors such as temperature. Following the constant-failure-mechanism assumption used in accelerated life testing, the characteristic parameters of cylinder characteristic parameters under standard operating conditions are predicted. Results show that this method is effective for life prediction using truncated small-sample data, overcoming the limitations of conventional approaches. Its applicability is proven in the life assessment of automatic ventilation doors, offering a robust tool for reliability. A reliability evaluation system for mine emergency control equipment is developed. This system provides real-time assessments and visualizations of equipment reliability, enhancing maintenance and management practices essential for mining operations. [ABSTRACT FROM AUTHOR]

Highly loaded Pt catalysts often suffer from poor oxygen reduction performance due to challenges in controlling the dispersion and particle size of Pt particles, with carbon carriers playing a crucial role in this aspect. Herein, N-doped carbon carriers were prepared through a solvothermal reaction, combined with continuous microwave-assisted technology to effectively manage the particle size and dispersion of Pt nanoparticles. The resulting highly loaded Pt catalysts demonstrated excellent activity and durability. The nitrogen-doped carbon not only reduced the size and concentration of Pt particles but also regulated the electronic structure of Pt, thereby enhancing the interaction between Pt and the carriers. The catalysts exhibited an electrochemical active area of 114 m2 g−1 Pt and a half-wave potential of 0.907 V. Following 30,000 accelerated durability tests, the mass activity decay rate was approximately 20%, surpassing that of commercial Pt/C catalysts. A peak power density of 1.22 W cm−2 was achieved in MEA under H 2 -Air conditions. Furthermore, the catalysts developed using nitrogen-doped modified carbon materials demonstrated the ability for large-scale production, holding promising potential for practical applications in proton exchange membrane fuel cells. • A unique approach enables batch production of high Pt loading catalysts. • Nitrogen-doped carbon optimized the size and distribution of Pt. • High-loaded Pt catalyst exhibits higher power density in H 2 -Air fuel cells. [ABSTRACT FROM AUTHOR]

This work reports the impact of gamma-ray (γ-ray) irradiation-induced degradation based on the trap behaviors in amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistors. By employing multiple measurement configurations via low-frequency noise and direct current I–V characterization, we quantitatively investigated the energetic distribution of subgap density-of-states in the a-IGZO channel and the spatial distribution of oxide traps (Not) in the gate insulator, respectively. Also, the qualitative analysis was performed to determine the oxygen-related defects after γ-ray irradiation using x-ray photoelectron spectroscopy. Furthermore, the validity of our results was additionally confirmed by measuring the breakdown voltage and applying positive-bias stress to the fabricated devices exposed to radiation for accelerated tests. [ABSTRACT FROM AUTHOR]

AbstractThis study investigates the behavior and reliability of CFRP-to-aluminum adhesive joints subjected to hygrothermal conditions under both natural and accelerated aging scenarios. Natural aging durations ranged from 1 to 3 years, while accelerated aging was performed over periods of 100–1200 h in 50-hour intervals. Fatigue life was evaluated using a three-point bending test, revealing a significant degradation in joint performance due to hygrothermal exposure. Key findings include a 25.98% reduction in fatigue life for samples naturally aged for three years and a comparable 27.33% reduction in samples subjected to 1000 h of accelerated aging. Hygrothermal conditions caused notable matrix degradation, transitioning failure modes from cohesive to mixed types (cohesive, adhesive, and fiber tear failures), with a direct impact on joint durability. Machine learning models, including artificial neural network (ANN), support vector regression (SVR), linear regression, polynomial regression, and random forest regression, were employed to predict natural aging durations based on accelerated aging data. Among these, the random forest regressor exhibited the highest predictive accuracy, effectively correlating accelerated aging durations to natural aging conditions. This study provides critical insights into the failure mechanisms and long-term performance of adhesive joints, offering a novel predictive approach to estimate natural aging effects from accelerated tests. These findings highlight the potential for optimizing joint designs to enhance durability and reduce failure risks in operational environments. [ABSTRACT FROM AUTHOR]

Grape pomace (GP) has gained attention for its potential to be valorized into functional foods due to its rich composition of bioactive compounds. In this work, GP has been exploited to develop plant-based mayonnaise alternatives and salad dressings. The influence of the water-to-oil ratio, percentage content of GP, lecithin, and vinegar on the viscosity and physical stability of the obtained emulsions have been investigated by the Design of Experiments. Two formulations, one high-oil (70%) and the second high-water (60%), were further studied for their potential applications. The selected samples were subjected to an accelerated stability test (60 °C for 21 days) to verify the influence of GP on oxidation protection. The high-water sample, combined with 8% GP, showed lower primary (peroxide value < 20 mEq O2/kg fat) and secondary oxidation (anisidine value < 55) parameters than the high-oil sample, highlighting the GP antioxidant activity. The phenolic profile of all samples by HPLC was also determined. Lastly, a sensory analysis was conducted, showing the highest overall acceptability for the oil-rich sample. The obtained results contribute to highlighting the potentiality of GP in the formulation of healthy foods, adopting the zero-waste approach for the full exploitation of this underutilized resource. [ABSTRACT FROM AUTHOR]

Non-noble metal electrocatalysts for the hydrogen oxidation reaction (HOR) that are both highly active and low-cost are essential for the widespread use of fuel cells. Herein, a simple two-step method for creating an in-plane heterostructure of Ni3N/MoSe2 loaded on N-doped reduced graphene oxide (Ni3N/MoSe2@N-rGO) as an effective electrocatalyst for the HOR is described. The process involves hydrothermal treatment of the Ni and Mo precursors with N-doped reduced graphene oxide, followed by the annealing with urea. The Ni3N/MoSe2@N-rGO catalyst exhibits high activities for the HOR, with current densities of 2.15 and 3.06 mA cm−2 at 0.5 V vs. the reversible hydrogen electrode (RHE) in H2-saturated 0.1 M KOH and 0.1 M HClO4 electrolytes, respectively, which is comparable to a commercial 20% Pt/C catalyst under similar experimental conditions. Furthermore, the catalyst demonstrates excellent durability, maintaining its performance during accelerated degradation tests for 5000 cycles. This work offers a practical framework for the designing and preparing of non-precious metal electrocatalysts for the HOR in fuel cells. [ABSTRACT FROM AUTHOR]

This article studies a method about how to design an efficient Bayesian sampling plan based on samples collected through a (n, t)-sampling scheme with a simple step-stress accelerated life test (ALT). For brevity, such a step-stress accelerated life test is called (n, t)-SSALT. A Bayesian sampling plan (BSP) derived through the (n, t)-SSALT is called BSPA. First, we derive the BSPA with data collected through a (n, t)-SSALT for a general loss function. Given gamma and Jeffreys prior distributions, an explicit expression of the Bayes decision function under a certain loss function is derived. By applying a curtailment procedure to the preceding Bayes decision function, an on-line new Bayes decision function and Bayesian sampling plan, called an efficient Bayesian sampling plan (EBSPA), are constructed. It is shown that the Bayes risk of EBSPA is less than or equal to that of BSPA. This indicates that the EBSPA is more efficient than the BSPA. Comparisons among some BSPAs and the proposed EBSPA are given. The numerical results indicate that, in terms of Bayes risks, the EBSPA significantly outperforms the BSPA. [ABSTRACT FROM AUTHOR]

The polymer-alloy geocell sheets (PAGS) represent a novel geocell material developed to replace conventional geocell materials. Accelerated creep testing, a convenient and precise performance evaluation method, presents a viable alternative to traditional creep testing for obtaining long-term creep strains. Nonetheless, there is a lack of prediction and in-depth exploration of accelerated creep testing. This paper aims to assess the efficacy of using the non-linear three-component (NLTC) model to simulate the accelerated creep behavior of PAGS. The predictive accuracy of the NLTC model has undergone evaluation through a comparison between stepped isothermal method (SIM) accelerated creep experimental tests and numerical simulations. Subsequently, the validated NLTC model was employed to simulate the time-temperature superposition method (TTSM), time-stress superposition method (TSSM), and stepped isostress method (SSM) accelerated creep tests, thereby verifying its effectiveness in predicting all accelerated creep tests. The results indicate that the NLTC model can effectively simulate creep deformation induced by temperature increases, particularly the temperatures below 41 °C. Although some errors are observed at elevated temperatures, it is within the acceptable range of 17.4%. Numerical simulation results of TTSM, TSSM, and SSM tests also suggest the model's proficiency in simulating the accelerated creep behavior by temperature and creep load increasing. • The accelerated creep behavior of polymer-alloy geocell sheets was investigated through experimental and numerical methods. • The suitability of the non-linear three-component model for simulating accelerated creep behavior was verified. • The non-linear three-component model was utilized to simulate all types of accelerated creep tests. [ABSTRACT FROM AUTHOR]

This study explores accelerated life tests to examine the durability of highly reliable products. These tests involve applying higher stress levels, such as increased temperature, voltage, or pressure, that cause early failures. The power half-logistic (PHL) distribution is utilized due to its flexibility in modeling the probability density and hazard rate functions, effectively representing various data patterns commonly encountered in practical applications. The step stress partially accelerated life testing model is analyzed under an adaptive type II progressive censoring scheme, with samples drawn from the PHL distribution. The maximum likelihood method estimates model parameters and calculates asymptotic confidence intervals. Bayesian estimates are also obtained using Lindley's approximation and the Markov Chain Monte Carlo (MCMC) method under different loss functions. Additionally, D- and A-optimality criteria are applied to determine the optimal stress-changing time. Simulation studies are conducted to evaluate the performance of the estimation methods and the optimality criteria. Finally, real-world datasets are analyzed to demonstrate the practical usefulness of the proposed model. [ABSTRACT FROM AUTHOR]

This study aims to explore the issues of evaluating the parameters and the accelerating factor based on constant stress for partially accelerating life tests when the potential failure times have an exponentiated Rayleigh distribution. Within the framework of progressive Type-II censoring schemes, we employ the Newton-Raphson algorithm as an iterative methodology to gain the maximum likelihood estimates, accompanied by proof of the existence of these point estimators. We also construct asymptotic confidence intervals for interested parameters and acceleration factors by utilizing the asymptotical characteristics of the maximum likelihood estimators. The Bayesian estimations of unknown parameters are derived by using the independent gamma priors and dependent Gamma-Dirichlet prior on the basis of square error and relatively smooth LINEX loss functions, respectively. Furthermore, we adopt the importance sampling method to compute Bayesian point estimates and the credible intervals with the highest posterior density. To validate the effectiveness of the suggested approaches, a series of simulated experiments are carried out. Lastly, we conduct analyzes on two actual datasets to show the applicability of the suggested techniques. [ABSTRACT FROM AUTHOR]

When conducting engineering life tests, it is common to collect necessary data from multiple production lines simultaneously. However, traditional methods are inadequate for analyzing this type of data, which is crucial for assessing reliability performance. In this study, we employ a newly proposed methodology called a joint Type-II hybrid censoring plan for gathering data from two production lines. We apply this plan to analyze three real-world engineering data sets when the parent distribution of the populations of interest is the Nadarajah–Haghighi distribution with varying shape and scale parameters. We consider two estimation approaches, maximum likelihood and Bayesian methods, to obtain point and interval estimates of the model parameters. The Bayesian estimates are obtained using the squared error loss function and the Markov Chain Monte Carlo procedure. To assess the performance of these different estimation methods, we conduct a simulation study that incorporates various testing plans. Finally, three engineering applications are considered to show the applicability of the offered methodologies. [ABSTRACT FROM AUTHOR]

The shelf life of meat products is a critical factor in ensuring both consumer safety and product quality. Traditional methods for determining shelf life are labor-intensive and time-consuming, making it challenging for manufacturers to adapt to market demands. The accelerated shelf life testing (ASLT) methodology offers a viable solution by exposing products to controlled elevated conditions that simulate long-term storage, allowing for faster shelf life predictions. This study evaluates the ASLT methodology as a predictive tool for determining the shelf life of high-pressure (HPP)-treated meat products. The present study includes experiments to verify the shelf life of frankfurter-type sausages under accelerated conditions. By simulating long-term storage at elevated temperatures (4–18 °C), a kinetic model was developed to monitor spoilage bacteria growth, with validation under dynamic temperature conditions. The results indicate that the main spoilage population of frankfurter-type sausages was lactic acid bacteria (LAB), which was strongly correlated with the total mesophilic microflora of the products. The findings show that elevated storage temperatures (8 and 18 °C) provide accurate shelf life predictions, offering an efficient approach to ensure product quality and meet consumer demands. [ABSTRACT FROM AUTHOR]

AbstractA one-shot device is a unit that performs its intended function only once. Actual lifetimes of such kind of devices cannot be observed. One can only observe if a failure occurred before or after a certain inspection time so the data is either left- or right-censored. Since one-shot devices are highly reliable products, accelerated life testing is commonly used to induce early failures. There are often more than one dependent failure modes causing the device to fail. Copula models have become one of the most popular tools for modeling dependence. In this paper, we provide statistical inference for modeling the dependence structure between failure modes in one-shot devices under constant stress accelerated life testing using copulas with Weibull marginals. The point estimates of the unknown parameters for the Weibull distribution along with the dependence parameter estimate are obtained using two estimation methods; the maximum likelihood estimation and the inference function for margins. Also, interval estimates are constructed using the asymptotic and bootstrap methods. The basic bootstrap and the studentized-t bootstrap intervals are obtained. Moreover, the survival probabilities are predicted under normal conditions. Numerical analysis including simulated data and a real life data are conducted to study the performance of the estimates. [ABSTRACT FROM AUTHOR]

The durability of reinforced concrete is associated with several factors that can trigger the corrosion of reinforcement bars. Among these factors, the most significant are chloride-ion attack and carbonation. This study evaluated, through accelerated testing, self-compacting concretes (SCCs) with reduced cement content in binary, ternary, and quaternary mixtures using high-early-strength Portland cement, fly ash (FA), metakaolin (MK), and hydrated lime (HL). These systems are proposed to address the slow compressive strength gains at 28 days in concretes with high fly ash content and to minimise the effects of carbonation in concretes with high levels of mineral additives. Laboratory tests were conducted to measure chloride-ion migration in a non-steady-state system, accelerated carbonation in a controlled chamber, electrical resistivity, void indices, and compressive strength. Based on the results obtained, it was found that the combined use of MK, FA, and HL was effective in reducing cement consumption to extreme levels, such as 120 and 150 kg/m3, while still achieving durability indices superior to those of SCCs with cement consumption of 500 kg/m3. [ABSTRACT FROM AUTHOR]

The proton exchange membrane integrity can be compromised during hot-press fabrication of membrane electrode assemblies (MEAs) causing premature cell failures during operation. In this work, infrared (IR) thermography was used as a diagnostic tool to spatially visualize hydrogen (H 2) crossover and identify process-induced-membrane irregularities (PIMs). These irregularities were identified as seed locations for MEA failures. Fine tuning of hot-press conditions was used to mitigate premature cell failures informed by accelerated stress testing (AST). The impact of PIMs on the initial performance, high-frequency resistances, open-circuit voltage, and H 2 crossover are reported. Nafion XL and 212 membranes, hot-pressed with a force of 16 kg/cm2 and temperature of 120 °C, were found to be consistently irregularity-free. Irregularity-free MEAs using Nafion 211, 212, and XL membranes demonstrated AST lifetime improvements of 58, 64 and 400%, respectively, compared to those fabricated with non-optimized conditions. This work highlights the importance of fabrication parameters on premature cell failures. • Process-induced membrane irregularities are seed locations for MEA failure. • Mitigated early onset failures through optimization of hot-press conditions. • Trade-offs between performance and durability are dependent on hot-press conditions. • IR thermography enabled correlation of failures to hot-press conditions. • Isolated material properties that influence durability from fabrication parameters. [ABSTRACT FROM AUTHOR]

The correct choice of a stone aggregate for railway ballast is directly related to the stability, safety, efficiency, and maintenance costs of the track. The aggregate must meet several criteria to ensure it is the most appropriate material. Thus, the present study aimed to evaluate four distinct stones: two granites, a diabase, and a basalt, all mined in the eastern region of the state of São Paulo, Brazil, regarding their applicability as ballast. Using Brazilian and ASTM procedures for stone samples, the tests were conducted on 55 and 75-mm specimens, in dry and wet conditions. As a result, all stones met the physical properties established by the standards. Among the mechanical properties, uniaxial compressive strength stood out, with all stones where the tested materials advantageously exceeding the 100 MPa required by the Brazilian standard. Regarding the accelerated weathering test with ethylene glycol, only basalt showed more significant changes, although its resistance to weathering was still lower than 10%. Our findings indicate that these stones perform adequately as ballast for railway applications. The study is expected to contribute to revisions of technical standards and the improvement of a database on Brazilian stone materials for use as railway ballast. [ABSTRACT FROM AUTHOR]

Lactic acid bacteria (LAB) are widely used to produce various food products, adding flavor, texture, and health benefits. The bacteria are commonly grown on expensive nutrients like glucose, sucrose, and yeast extracts, which makes them commercially unappealing. In the current study, Lactobacillus acidophilus TISTR 1338 culture was studied using spent cell yeast as a nitrogen source and molasses as a carbon source. The drying process used to create starter cultures of Lactobacillus acidophilus TISTR 1338 was vacuum drying. After vacuum drying, this bacterium had a survival rate of 8.08 log CFU/g. The dried strain survived for four months at 37 °C. With wasted cells at 0.5%, molasses concentration at 11% at 2.14 109 CFU/mL at 22 h, precise growth rate at 0.39 h−1, and yield cell mass at 1.67 1011 CFU/g sugar, yeast produced the maximum cell mass. The lower viability of the tested strain was induced by a higher temperature during this prolonged storage. Meanwhile, dehydrated starter culture was subjected to accelerated storage testing at 50, 60, and 70 °C. To determine the vacuum-dried Lactobacillus acidophilus TISTR 1338′s long-term storage viability, a temperature-dependent prophecy model was created. Molasses and spent cell yeast serve as promising carbon and nitrogen sources when optimized conditions are employed. The study also suggests that vacuum drying is a promising method for producing dried cells suitable for non-refrigerated storage conditions. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the sensorial, physicochemical, rheological, and microbiological properties of yoghurt fortified with Artemisia absinthium leaf powder during refrigerated storage. The valorization of this plant in food industry was realized by the incorporation of its dried leaf powder at various concentrations in order to produce a new functional yoghurt. It is interesting to note that the fortified yoghurt with the lowest Artemisia dose (2%) was the most preferred by the panel. Furthermore, this fortification did not affect the fermentation parameters nor the viability of lactic starter. During storage, the incorporation of Artemisia powder reduced syneresis and improved the microbiological properties of fortified yoghurts. Besides, at the end of storage, it was noted that yoghurt fortified with 2% of Artemisia powder presented the highest consistency (8.98±0.04 Pa sn) and antioxidant activity (60.08±3.61%) when compared to the control yoghurt. Finally, the accelerated shelf-life test showed the efficiency of Artemisia absinthium powder incorporation by increasing the shelf life of yoghurt by about 4 days. [ABSTRACT FROM AUTHOR]

Conventional phosphoric acid (PA) doped polybenzimidazole are regarded as the most promising materials for high‐temperature proton exchange membrane fuel cells (HT‐PEMFCs). Yet, their practical application has been hindered by their high production cost, poor oxidation stability, and loss of PA at low temperatures. Here, a polymer of intrinsic microporosity containing "sulfide‐linkage" radical‐sacrificial‐agent is designed with good solubility and high PA retention, which enables it to operate for long periods at 80–180 °C. Specifically, the "sulfide‐linkage" radical‐sacrificial‐agent enabled PSBI‐IM to be durable for 100 h with mass retention still higher than 90%, and the capillary effect of the micropores enabled PSBI‐IM/PA to retain more than 60% of PA under high humidity. After rational optimization, the cell assembled with PSBI‐IM/PA achieved a power density of 1.62 W cm−2 with a specific power of 2.7 W mg−1 and an operating time of more than 500 h (0.2/0.4 A cm−2@160 °C). In addition, the voltage drop is only 5% even after 40 h of accelerated stress testing at 0.4 A cm−2@ 80 °C. Therefore, the PSBI‐IM/PA can be stabilized over a wide temperature range from 80 to 160 °C, providing a new material for the HT‐PEMFCs with flexible operational temperature. [ABSTRACT FROM AUTHOR]

• An accelerated experimental method for quickly realizing the water fouling process was designed. • Water fouling process experiences the initiation, growth and stabilization stages in sequence. • 5 mm tubes are more prone to form water fouling compared with 7 mm tubes. • Screwed tubes are benefit to destroy the integrality of fouling layer compared with smooth tubes. • Fouling mass in the 5 mm smooth tube is larger than that in other types of tubes. Application of copper tubes with the diameter of 5 mm instead of 7 mm in chillers of central air conditioning systems is the development tendency due to the requirement of copper material saving. However, the heat transfer deterioration by water fouling precipitated in 5 mm tubes may be more serious than that in 7 mm tubes. The purpose of this paper is to comparatively investigate the water fouling characteristics on both 5 mm and 7 mm tubes. An accelerated experimental method of water fouling process was designed to quickly evaluate the fouling degree. Four tube types are tested, i.e. a 7 mm smooth tube, a 7 mm screwed tube, a 5 mm smooth tube and a 5 mm screwed tube, and these tubes are fabricated as flexible coiled tubes with total length of 200 cm. The results show that the water fouling process experiences the initiation, growth and stabilization stages in sequence, and the crystal form of fouling is in the vaterite, aragonite and schistosity patterns respectively. The fouling masses in 5 mm smooth tube and 5 mm screwed tube are respectively 42.1% and 16.9% larger than those in 7 mm smooth tube and 7 mm screwed tube, meaning that 5 mm tubes are more prone to form water fouling compared with 7 mm tubes; while the averaged fouling mass in screwed tubes is 2.8% lower than that in smooth tubes since screwed tubes are benefit to destroy the integrality of fouling layer and enhance the removal of deposited particulates. [ABSTRACT FROM AUTHOR]

Cement-stabilized rammed earth (CSRE) finds applications in structural walls. The CSRE walls subjected to compression and flexure show brittle failures. The inclusion of short fibers into the CSRE matrix enhances the straining capacity and postcrack response, promoting ductile failures. Although the effect of fiber reinforcement on the mechanical behavior of the fiber-reinforced CSRE composites has been well explored, there are limited focused studies on the durability of natural fiber–reinforced CSRE composites. Establishing the durability of such composites is essential for promoting the use of natural fibers in CSRE construction. The present study focuses on the durability of coir fiber–reinforced CSRE elements. The investigations examined (1) the durability of coir fibers in the highly alkaline environment, (2) the interfacial bond strength of coir fibers in the CSRE matrix subjected to accelerated weathering tests, and (3) strength, stiffness, straining capacity, and postpeak response after subjecting the composite to accelerated durability tests. The investigations revealed that after exposure to accelerated cyclic weathering tests (1) the fiber–matrix bond strength in the CSRE composite is partially reduced, (2) there is a marginal variation in compressive strength and increased stiffness, (3) the composite retains a considerable amount of straining and energy absorption capacity, and (4) it shows satisfactory durable characteristics. Investigations revealed that the coir fiber–reinforced CSRE composite is a durable material. [ABSTRACT FROM AUTHOR]

This study introduces a novel approach to accelerated life test experiments by examining competing risk factors using the Tampered Random Variable (TRV) model. This approach remains extensively unexplored in current research. The methodology is implemented for a simple step-stress life test (SSLT) model and accounts for various causes of failure. The Power Chris–Jerry (PCJ) distribution is utilized to model the lifetimes of units under different stress levels, incorporating unique shape parameters while maintaining a fixed-scale parameter. This study employs the TRV model to integrate constant tampering coefficients for each failure cause within step-stress data analysis. Maximum-likelihood estimates for model parameters and tampering coefficients are derived from SSLT data, and some confidence intervals are presented based on the Type-II censoring scheme. Furthermore, Bayesian estimation is applied to the parameters, supported by appropriate prior distributions. The robustness of the proposed method is validated through comprehensive simulations and real-world applications in different scientific domains. [ABSTRACT FROM AUTHOR]

In a different area of life testing, designing experiments needs higher stress level than normal stress one. Also, the time to failure of experimental units is resulted by one of a fetal risk factors, only. In this paper, we consider the simple step-stress model with competing risks under Type-I censoring. The cumulative exposure model is assumed when the lifetime of test units follows Rayleigh distribution. Under this setup, we obtain the maximum likelihood estimates and the Bayes Estimators of the unknown parameters using Markov chain Monte Carlo (MCMC) method under various loss functions. Furthermore, to demonstrate the proposed methods, dataset is analyzed. Also, the confidence intervals are derived by using the asymptotic distributions of the maximum likelihood estimates. For comparison, we obtain the highest posterior density (HPD) credible intervals based on different prior distributions. Their performance is assessed through Monte Carlo simulations. [ABSTRACT FROM AUTHOR]

In recent studies comparing the outdoor weathering of poly(vinylidene fluoride) (PVDF)-based coatings against several accelerated weathering test cycles, including ASTM D7869-13, we found all the cycles accurately reproduced Florida rank order gloss and color retention trends for PVDF-based coatings made with single (non-TiO2) pigments. However, none of the cycles accurately predicted the rank order of rutile TiO2 grades for Florida gloss retention, nor the magnitude and direction of color fade in organic pigment/inorganic pigment blends. This paper follows up on these earlier studies, to examine whether the ASTM D7869 cycle might nevertheless have some utility for industry standard or specification purposes, across resin lines. We report for the first time the results of two recent studies comparing ASTM D7869 and South Florida weathering, for a range of weatherable binder chemistries commonly used in industrial coatings, and specifically examining color-matched, non-white colors. The data suggest that ASTM D7869 testing for 5000–6000 h might be a promising way to gauge the weatherability of coatings intended to meet 5-year South Florida weathering requirements. At the same time, the data also suggest that the ASTM D7869 cycle would be unreliable for predicting the weatherability of coatings intended to last 10 years or even much longer, within a 6–12-month timeframe, due to issues with false positives. For this reason, in the new SSPC Paint 47 fluoropolymer topcoat standard, a more aggressive UVB-313 fluorescent cabinet cycle was chosen, due to its ability to give results in 6 months, with a very low level of false positives. [ABSTRACT FROM AUTHOR]

The paper presents a new approach towards forming Ce-based nanostructures using deep eutectic solvents (DESs) as new green solvents and large-scale media for the chemical and electrochemical synthesis of advanced functional surfaces and nanomaterials. Some experimental results regarding the cathodic electrodeposition of cerium-based conversion coatings onto AA7075 aluminum alloys involving different DES-based formulations are discussed. Electrolytes containing Ce(NO3)3·6H2O dissolved in choline chloride-glycerine and choline chloride-urea (1:2 molar ratio) eutectic mixtures with additions of H2O2 have been proposed and investigated. The influence of the operating parameters, including the applied current density, process duration and temperature on the quality of the formed Ce-containing conversion layers was studied. Adherent and uniform Ce-based conversion layers containing 0.3–5 wt.%. Ce have been obtained onto Al alloy substrates. Higher values of the applied current density and longer process durations led to higher Ce content when a choline chloride-urea eutectic mixture was used. Several accelerated corrosion tests were performed to evaluate the corrosion performance, respectively: (i) continuous immersion in 0.5 M NaCl for 720 h with intermediary visual examinations, recording of (ii) potentiodynamic polarization curves and of (iii) impedance spectra at open circuit potential in 0.5 M NaCl, as well as (iv) salt mist test for 240 h. The influence of an additional post-treatment step consisting in the electrochemical deposition of a hydrophobic Ce-based layer involving ethanolic solutions of stearic acid and cerium nitrate is also considered. Different corrosion performances are discussed, taking into account the used DES-based systems and electrodeposition parameters. [ABSTRACT FROM AUTHOR]

Parts produced using material extrusion (MEX), a common additive manufacturing method, are often limited to non-structural applications due to sub-optimal mechanical properties, including poor interlayer fracture toughness, Gc. Gc of MEX parts depends on process parameters, but the complex relationships between process parameters and Gc are not well understood. This paper describes the use of a machine learning (ML) method using Forests with Uncertainty Estimates for Learning Sequentially (FUELS) to study the effect of five process parameters on the Gc of MEX parts. Training data for the FUELS model is collected using a modified double cantilever beam (MDCB) test, and Gc is calculated using a classical beam theory approach. The FUELS method provides guided testing by suggesting additional parameter combinations from high-uncertainty regions of the parameter space. After sequentially testing a total of 2.9% of the 2205 possible parameter combinations, there was minimal change in the non-dimensional model error, and training was concluded. Gc values collected from testing ranged 0.056 kJ/m2 to 1.774 kJ/m2. The resulting parameter space was examined to better understand how Gc evolves with changing process parameters. Among other results, extrusion temperature was shown to have a greater effect on Gc at higher print speeds. Overall, the FUELS method, paired with accelerated experimental testing, provides a useful means of quickly exploring the large MEX parameter space to establish relationships among process parameters and Gc. The methods of this study can serve as a blueprint for other studies with large parameter spaces, not just in MEX but in other manufacturing processes. [ABSTRACT FROM AUTHOR]

With the developments of the electronic industry, efforts to achieve high DC insulating reliability are underway to improve the mean time to failure (MTTF) of multilayer ceramic capacitors (MLCCs). However, there are few studies on appropriate measuring methods to evaluate their different reliability characteristics quantificationally. This study measured different reliability characteristics of BaTiO 3 -based multilayer ceramic capacitors sintered at three different temperatures with highly accelerated life tests (HALTs). Kaplan–Meier survival analysis, two-parameter Weibull fitting, and a new method using a stud genetic algorithm were used to calculate their MTTF in HALT conditions, and the comparison among them was carried out to select a proper fitting way. With the appropriate method, their MTTF at the rated condition was predicted and compared. Their conduction modes were also differentiated to explain their aging sensitivities to temperature and voltage. As a result, a proper way to evaluate the sample's reliability characteristics with a bathtub curve was established, and the best sintering temperature for capacitance that is also the best for reliability at the rated condition was confirmed. Meanwhile, different conducting models of MLCCs were also proved to be related to their insulation stability. [ABSTRACT FROM AUTHOR]

High-temperature proton exchange membrane fuel cells (HT-PEMFCs) offer solutions to challenges intrinsic to low-temperature PEMFCs, such as complex water management, fuel inflexibility, and thermal integration. However, they are hindered by phosphoric acid (PA) leaching and catalyst migration, which destabilize the critical three-phase interface within the membrane electrode assembly (MEA). This study presents an innovative approach to enhance HT-PEMFC performance through membrane modification using picosecond laser scribing, which optimises the three-phase interface by forming a graphene-like structure that mitigates PA leaching. Our results demonstrate that laser-induced modification of PA-doped membranes, particularly on the cathode side, significantly enhances the performance and durability of HT-PEMFCs, achieving a peak power density of 817.2 mW cm⁻² after accelerated stress testing, representing a notable 58.2% increase compared to untreated membranes. Furthermore, a comprehensive three-dimensional multi-physics model, based on X-ray micro-computed tomography data, was employed to visualise and quantify the impact of this laser treatment on the dynamic electrochemical processes within the MEA. Hence, this work provides both a scalable methodology to stabilise an important future membrane technology, and a clear mechanistic understanding of how this targeted laser modification acts to optimise the three-phase interface of HT-PEMFCs, which can have impact across a wide array of applications. High-temperature proton exchange membrane fuel cells offer efficient solutions to complex fuel cell challenges, including fuel flexibility and heat management. Here the authors demonstrate that laser-scribed membranes improve fuel cell durability and boost peak power density by over 50%, providing a more stable and scalable approach for high performance fuel cells. [ABSTRACT FROM AUTHOR]

Investigating the chemical and mechanical degradation phenomena of polymer electrolyte membranes (PEMs) is crucial, as they significantly influence the electrochemical performance and lifetime of fuel cell electric vehicles. For this, the combined use of chemical and mechanical accelerated stress test (AST) protocols has proven effective and reliable in evaluating PEMs durability within a relatively short period. However, it remains unclear whether the combined AST protocols exclusively affect PEMs durability, since the AST evaluation is performed not in the membrane states but in the membrane-electrode assembly (MEA) state. To address this question, a combined AST protocol consisting of a single cycle involving a chemical degradation phase followed by a mechanical degradation phase, was applied. The influence of the combined AST on both the membrane and electrodes was investigated using a variety of electrochemical evaluations conducted after each cycle. Additionally, the study includes changes in the physical characteristics of each MEA component. This study deals with the degradation behavior of MEA obtained after a combined chemical/mechanical accelerated stress test to evaluate the membrane durability for polymer electrolyte fuel cells. [Display omitted] • Combined chemical/mechanical AST impact on PEMFC membrane and electrodes. • Electrochemical and physical characteristics are monitored as the AST progresses. • Chemical and mechanical degradation analyzed from membrane and electrode perspectives. [ABSTRACT FROM AUTHOR]

The interplay between i) cathodic electrocatalytic layer (EC layer) features of proton exchange membrane fuel cell (PEMFC), focusing on the oxygen reduction reaction (ORR) electrocatalyst (EC) and the Pt loading; and ii) the PEMFC performance and durability is evaluated. An innovative hierarchical “core–shell” carbon nitride multimetallic ORR electrocatalyst (“PtCuNi/C” H‐EC) is compared with a conventional Pt/C benchmark. The various contributions to PEMFC performance at beginning of test (BOT) are isolated and correlated to the physicochemical features of the ORR EC and the cathodic EC layer. The PEMFC durability is investigated extensively via accelerated stress tests (ASTs) mimicking long‐term operation. Particular attention is dedicated to determine how ageing affects: i) PEMFC cell voltage; and ii) the cathode electrochemically active surface area (ECSA). “Post‐mortem” studies are carried out to probe how ageing influences the cathodic EC layer features, including: i) chemical composition; ii) elements distribution; iii) EC morphology; and iv) structure and crystal size of the Pt‐based metal nanoparticles bearing the active sites. Integrating the experimental results allows to identify both the positive and the detrimental effects triggered by the introduction of transition metals (TMs) in the ORR EC on the factors modulating PEMFC performance and long‐term operation. [ABSTRACT FROM AUTHOR]

ABSTRACT Thanks to the extensive applications of accelerated degradation tests (ADT), the influence of covariates has been paid more and more attention. We propose a power‐law form, which is studied with other previously perceived covariate types for model uncertainty not neglecting unidentified distribution of drift parameter. It simultaneously determines the distribution of volatility parameters under Wiener process (WP) when the dependency inner model's parametric space exists. The Markov Chain Monte Carlo (MCMC) algorithm implemented by WinBUGS is employed to deal with general failure possibility functions of multiple hypothesis combinations. A new criterion aimed at measuring the volatility variable's goodness‐of‐fit is involved a company with several Akaike information criterion (AIC)‐like indexes for an overall model comparison and selection. It is convincing that after several numerical and real example analyses, the interaction between the covariate and latent variable distribution influences the performance of computation to a large degree. [ABSTRACT FROM AUTHOR]

Despite significant advances in perovskite solar cells (PeSCs), the operational instability and susceptibility to Pb leakage of PeSCs severely limit their widespread application. To address these issues, this study investigates the effect of doping the Spiro‐OMeTAD hole‐transporting layer (HTL) with a chemically‐modified 2D conjugated covalent organic framework (Tp‐Azo‐COF) on the photovoltaic performance and stability of PeSCs. Enriched with abundant carbonyl (C═O) groups and azo (N═N) nodes, Tp‐Azo‐COF has excellent chelation and adsorption capabilities, and experimental results confirm that Tp‐Azo‐COF effectively decreases Pb leakage and Li‐ion migration, improving the environmental safety and operational stability of PeSCs. The optimized PeSCs (0.12 cm2) exhibit an efficiency of 24.25%, a new benchmark for COF‐modified devices, and maintain robust performance in large‐area modules (18 cm2) with an efficiency of 21.96%. Under accelerated aging tests, including continuous light irradiation at maximum power point tracking for 980 h, the module demonstrated exceptional durability, with near‐100% efficiency retention. The COF doping strategy developed in this study significantly enhances operational stability and minimizes Pb leakage in PeSCs, paving the way for the sustainable, large‐scale deployment of perovskite photovoltaics. [ABSTRACT FROM AUTHOR]

Several methods have been proposed for the accelerated carbonation test of concrete, but there is no consensus on the best procedure for preconditioning the specimens. Thus, this study aims to assess the effects of four preconditioning methods - ISO 1920-12:2015, EN 13295:2004, XP P 18-458:2008 and RILEM TC 116-PDC:1999 - on the accelerated carbonation test. Four different concrete mixtures were used to ensure variations in mechanical strength and porosity. The specimens were subjected to accelerated carbonation in a chamber with 3% CO2, 65% RH and 23 °C for 14, 28 and 42 days, so that a database of 1536 carbonation measurements was produced. Internal and surface moisture of the concrete were measured at various stages throughout the experiment. Statistical analysis revealed that the preconditioning method significantly impacted the concrete's carbonation rate - Fcalc (126.68) ≫ Ftab (2.61), with p-value ≅ 0. Preconditioning affected the concrete's moisture content at the beginning of the process, and inverse linear relationships were found between concrete surface moisture and carbonation depth (0.85 ≤ R2 ≤ 0.99). The study points to the usefulness of the surface moisture technique to monitor specimens during carbonation tests, and it concluded that XP was the best among the four methods studied. [ABSTRACT FROM AUTHOR]

Most current international standards for qualifying polymer-insulated wires for aircraft applications rely on degradation tests conducted under standard pressure conditions. However, some wires are used in unpressurized areas and therefore need to withstand low-pressure conditions. In the technical literature, there is a shortage of data on this topic. This article focuses on accelerated wet arc tracking tests of insulated wires and evaluates three methods that assess the performance of surface discharges generated during degradation, based on the light emitted, under different pressure conditions in the range of 100 kPa–16 kPa. The experimental results presented in this paper show that the sensitivity of the proposed methods increases with atmospheric pressure, allowing a better quantification of the degradation effects at higher pressures. These results can also help to gain experience and understanding in how commercial optoelectronic sensors can be used to assess the insulation condition by analyzing the light generated by the surface discharges. [ABSTRACT FROM AUTHOR]

We propose a parametric model for describing chronic disease mortality from cohort data and illustrate its use for Type 2 diabetes. The model uses ideas from accelerated life testing in reliability theory and conceptualizes the occurrence of a chronic disease as putting the observational unit to an enhanced stress level, which is supposed to shorten its lifetime. It further addresses the issue of semi‐competing risk, that is, the asymmetry of death and diagnosis of disease, where the disease can be diagnosed before death, but not after. With respect to the cohort structure of the data, late entry into the cohort is taken into account and prevalent as well as incident cases inform the analysis. We finally give an extension of the model that allows age at disease diagnosis to be observed not exactly, but only partially within an interval. Model parameters can be straightforwardly estimated by Maximum Likelihood, using the assumption of a Gompertz distribution we show in a small simulation study that this works well. Data of the Cardiovascular Disease, Living and Ageing in Halle (CARLA) study, a population‐based cohort in the city of Halle (Saale) in the eastern part of Germany, are used for illustration. [ABSTRACT FROM AUTHOR]

The assessment of PEM water electrolyzer (PEMWE) degradation is essential for understanding their long-term durability and performance under real-world conditions. This research focuses on the fluoride emission rate (FER) as a crucial parameter during PEMWE operation. Two different FER analysis methods were evaluated, considering their feasibility and ease of integration into a PEMWE system. Various stressors were examined to gain insights into membrane degradation and explore potential mitigation strategies. The utilization of a photometric detection method allowed for the quantification of FER in each test. Results highlight a noteworthy correlation between applied stressors and FER, with variations depending on specific test conditions. An accelerated stress test conducted for 100 hours revealed a high FER at the anode of 0.83 μg h−1 cm−2 during the initial phase. Correspondingly, energy dispersive X-ray (EDX) mapping showed a reduction in Nafion™ content on the catalyst-coated membrane (CCM) surfaces, likely impacting proton conductivity and performance. Electrochemical results further support these findings, indicating performance changes corresponding to the observed membrane degradation. [ABSTRACT FROM AUTHOR]

Carbon nitride photocatalysts are among the most studied candidates for efficient solar hydrogen (H2) production due to their abundance of precursors, suitable bandgap, and visible light utilization. However, the polymeric nature of carbon nitride materials raises concerns regarding the self‐decomposition during photocatalytic redox processes. Yet, the operational stability of carbon nitride photocatalysts for solar H2 production remains under‐explored. Here we evaluate the photostability of carbon nitride photocatalysts with platinum (Pt) as the co‐catalyst for solar H2 evolution and significant deactivation of this photocatalyst is observed under'accelerated' testing conditions. It is demonstrated that the detachment of the Pt co‐catalyst on the surface of carbon nitride is the major reason for this deactivation, which can be attributed to a synergistic effect of photo‐corrosion and mechanical stirring. The photo‐corrosion weakens the interfacial bonding between carbon nitride and Pt co‐catalyst, while continuous collisions from the mechanical stirring promote the detachment of co‐catalysts from the surface of carbon nitride. These understandings provide insights into the rational design of photocatalysts and photocatalytic systems for improved operational stability. [ABSTRACT FROM AUTHOR]

To tackle the nonlinear radiation distortions (NRDs) in multimodal remote sensing images, this letter proposes a multimodal remote sensing image registration method that utilizes phase symmetry and rank-based local self-similarity (LSS). First, the local phase information of the images is utilized to construct a phase symmetry map, which is then used to detect features using the Features from Accelerated Segment Test (FAST) algorithm. Subsequently, a new feature descriptor that combines rank-based local self-similarity and phase congruency, is generated. Finally, the Fast Sample Consensus (FSC) method is employed to eliminate outliers. Experimental results on publicly available multimodal remote sensing image datasets demonstrate that the proposed method outperforms the state-of-the-art methods in terms of number of correct matches, precision, and root mean squared error (RMSE). [ABSTRACT FROM AUTHOR]

A cell's ability to store energy, and produce power is limited by its capacity fading with age. This paper presents the findings on the performance characteristics of prismatic Lithium-iron phosphate (LiFePO4) cells under different ambient temperature conditions, discharge rates, and depth of discharge. The accelerated life cycle testing results depicted a linear degradation pattern of up to 300 cycles. Linear extrapolation reveals that at 25°C temperature, an increase in the discharge rate from 0.5 C to 0.8 C reduces the cycle life significantly by 52.9%. On the other hand, at a constant discharge rate, an increase in temperature reduced predicted cycle life in the range of 23.2–41.36%. Lithium-ion cells' reliability modeling and analysis was carried out using an exponential distribution showing the increasing failure rate with age, with the temperature significantly reducing the expected life of the cells. [ABSTRACT FROM AUTHOR]

In reliability and life analysis, the accelerated life test is frequently used because it can reduce cost and obtain additional reliability and lifetime information. In addition, when a unit fails in a life test, there are often two or more risk factors related to the cause of the failure. In this article, we consider the inference from a step-stress-accelerated life test with competing risks using progressive type-II censored data. Based on the assumption that the parameters affected by stress follow a log-linear model with the stress level, the proportional hazard model with the Kumaraswamy distribution is established. The point estimation of the unknown parameters is derived using maximum likelihood and Bayesian methods. Accordingly, the logarithmic asymptotic confidence and the highest posterior density credible intervals are derived and constructed. Moreover, the algorithm for multi-parameter sampling and simulation technology based on this model is given. Simulation results show that the proposed methods have good performance. In light of the estimates of the parameters, the estimated reliability function under normal conditions can be expressed, and its images under different methods are drawn. Last, a real dataset and a set of simulated data are presented for illustrative purposes. [ABSTRACT FROM AUTHOR]

To resolve the problems such as fatigue or pitting corrosion on a low-cost evaporator tubing in a household refrigerator, the tube material was changed from copper (Cu) to Aluminum (1070 Al) by applying parametric accelerated life testing (ALT). This systematic strategy included the following: (1) ALT plan used on BX lifetime that will be X percent of the accumulated failure, (2) corrosion effect modeling, (3) ALTs with revision, and (4) estimation whether the design attained the objective BX lifetime. A quantum-transported life-stress model and a sample size producing reliability quantitative (RQ) statements were proposed. A case study investigation for this methodology was employed to enhance the lifetime of a household refrigerator whose evaporator tubing was failing in the field due to aqueous pitting or crevice corrosion. In the first ALT, for RQ statements, this failure was reproduced by ALT equipment and the refrigerator tubing that were placed in a 3.5% saline solution for the accelerated condition. The pitted tubing was determined to be nearly identical to those returned from the marketplace refrigerators. Using a scanning electron microscope (SEM) with Energy Dispersive X-ray (EDX) showed that the trouble with the evaporator tubing came from water condensation and direct chlorine contact on polyvinyl chloride (PVC) tape with water-soluble adhesives layer. Three action plans were evaluated. First, the tape material was changed from PVC to polyethylene (PE) with a water-soluble adhesive. Second, the contraction tube was enlarged from 50 to 200 mm. Third, polyethylene foam pads between enclosure case and the tubing were inserted. In the 2nd ALT, the refrigerator tubing showed no corrosion. Refrigerator thus achieved the goaled lifetime—B1 life of ten years. [ABSTRACT FROM AUTHOR]