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Objectives: This study aimed to investigate the effect of a customized low-sodium bioactive glass (BG) fillers in experimental resin composites on their bond strength to dentin after 12 months of artificial aging. Specifically, it evaluated whether the bond strength was affected by different BG concentrations (0, 10, 20, 40 wt%) and artificial aging durations (1, 6, and 12 months). Materials and methods: Experimental composites were prepared with 10, 20, and 40 wt% of a customized low-sodium fluoride-containing BG. The experimental composite with 0 wt% BG was used as a control, while Beautifil II (Shofu) was used as an external reference material. A universal adhesive system was applied to dentin substrates and composite build-ups were made. Bond strength was measured using a macro-shear bond strength test, and Weibull statistics were used to assess the reliability of the materials. Failure modes were analyzed to evaluate the type of the fracture. Results: After 12 months, the bond strength of all experimental composites remained stable and comparable to the control material, with statistically significant improvements between 6 and 12 months for all experimental materials. The bond strength was statistically similar across materials, except at the 12-month point, where the 20 wt% BG-composite showed significantly higher bond strength than the 40 wt% BG-composite. The frequency of mixed failures in composite increased after 12 months, particularly in experimental composites containing higher BG content. Conclusions: The incorporation of a customized low- sodium BG into resin composites did not negatively impact their bond strength to dentin over 12 months. Instead, bond strength improved over time, and the composites remained mechanically stable, although a higher incidence of mixed failures was observed with increased BG content. Clinical relevance: The customized low-sodium BG demonstrated stable bond strength over the 12-month period, offering a promising option for functional fillers in restorative composites without compromising the longevity of the adhesive-dentin interface. [ABSTRACT FROM AUTHOR]

This paper investigates the failure mechanism of the rear drive shaft in a modified pickup truck which had operated for about 3000 km. The investigation included macroscopic and microscopic evaluation to document the morphologies of the fracture surface, measurement of the material composition, metallographic preparation and examination, mechanical testing, and finite element modelling and calculations. The results obtained suggest that rotation-bending fatigue was the primary cause of the drive shaft failure. The crack initiation is located in the root of the machined threads on the drive shaft surface and expanded along the side of the machining line surface. The main cause of fatigue cracks is attributable to a high stress concentration owing to a large unilateral bending impact under overload. Meanwhile, the bidirectional torsional force also produces a higher stress concentration and thus accelerates the fatigue crack to expand radially along the surface. Furthermore, the hardness of the central section of the drive shaft was marginally below standard. This deficiency results in harm to the bearings and other mechanical components, as well as expediting the enlargement of cracks. Finite element analysis revealed significant contact stress between the bearing and drive shaft, with stress levels exceeding the fatigue limit stress of the parent material. This highlights the need for reevaluation of the heat treatment process and vehicle loading quality to enhance the drive shaft's longevity. [ABSTRACT FROM AUTHOR]

Novel hybrid laminates consisting of carbon fiber-reinforced polymers and steel plate cold commercial (CFRP-SPCC) have been successfully manufactured and tested in the present study. Four different tests have been made i.e., tensile test, flexural test, double cantilever beam (DCB) or Mode I test, and end notched flexure (ENF) or Mode II test. After being tested, these samples need to be evaluated. Hence, an inappropriate evaluation step while identifying the cause of failure of the failed specimens can create a false conclusion. The present study aims to systematically evaluate the fractured specimens of CFRP-SPCC in different tests (tensile, flexural, DCB, and ENF test) using different tools, i.e., pocket camera, digital microscope, light microscope, and Scanning Electron Microscopy (SEM). The results showed, in terms of tensile, the highest strength occurred with 1475.4 MPa. In comparison, the highest flexural strength occurred with 1516.1 MPa, while DCB and ENF showed the highest values with 116.4 and 330 J/m2, respectively. Furthermore, the results showed that digital and light microscopes are satisfied to evaluate the specimen in tensile test. However, for the flexural test, ENF, and DCB test, besides the light microscope, further analysis using SEM-EDX is recommended to evaluate the specimen after failure.

Material selection is a crucial aspect in the design of reliable, efficient and long-lasting wave energy converters (WECs). However, to date, the development of tailored methodologies applied to the material selection of WECs remains vastly unexplored. In this paper, a material selection framework for the case of lift-based WECs is developed. The application of the methodology is demonstrated with the hydrofoils of the device. Offshore steel, high-strength offshore steel, aluminium alloys, and carbon- and glass-fibre-reinforced composites are considered and evaluated subject to relevant criteria for wave energy converters, namely structural reliability, hydrodynamic efficiency, offshore maintainability, total manufacturing cost and environmental impact. Candidate materials are assessed via fuzzy TOPSIS for three scenarios of the life cycle of the WEC: conceptual, commercial and future projection stages. Results show that the choice of optimal materials could change from present to future and that multi-criteria decision-making tools aided by a fuzzy approach are useful design tools for novel WECs when field data are scarce. Hence, methodologies such as the ones presented in this work can help in reducing the probability of mechanical failures of emerging WEC technology. [ABSTRACT FROM AUTHOR]

This paper investigates the failure mechanism of the rear drive shaft in a modified pickup truck which had operated for about 3000 km. The investigation included macroscopic and microscopic evaluation to document the morphologies of the fracture surface, measurement of the material composition, metallographic preparation and examination, mechanical testing, and finite element modelling and calculations. The results obtained suggest that rotation-bending fatigue was the primary cause of the drive shaft failure. The crack initiation is located in the root of the machined threads on the drive shaft surface and expanded along the side of the machining line surface. The main cause of fatigue cracks is attributable to a high stress concentration owing to a large unilateral bending impact under overload. Meanwhile, the bidirectional torsional force also produces a higher stress concentration and thus accelerates the fatigue crack to expand radially along the surface. Furthermore, the hardness of the central section of the drive shaft was marginally below standard. This deficiency results in harm to the bearings and other mechanical components, as well as expediting the enlargement of cracks. Finite element analysis revealed significant contact stress between the bearing and drive shaft, with stress levels exceeding the fatigue limit stress of the parent material. This highlights the need for reevaluation of the heat treatment process and vehicle loading quality to enhance the drive shaft’s longevity.

Novel hybrid laminates consisting of carbon fiber-reinforced polymers and steel plate cold commercial (CFRP-SPCC) have been successfully manufactured and tested in the present study. Four different tests have been made i.e., tensile test, flexural test, double cantilever beam (DCB) or Mode I test, and end notched flexure (ENF) or Mode II test. After being tested, these samples need to be evaluated. Hence, an inappropriate evaluation step while identifying the cause of failure of the failed specimens can create a false conclusion. The present study aims to systematically evaluate the fractured specimens of CFRP-SPCC in different tests (tensile, flexural, DCB, and ENF test) using different tools, i.e., pocket camera, digital microscope, light microscope, and Scanning Electron Microscopy (SEM). The results showed, in terms of tensile, the highest strength occurred with 1475.4 MPa. In comparison, the highest flexural strength occurred with 1516.1 MPa, while DCB and ENF showed the highest values with 116.4 and 330 J/m2, respectively. Furthermore, the results showed that digital and light microscopes are satisfied to evaluate the specimen in tensile test. However, for the flexural test, ENF, and DCB test, besides the light microscope, further analysis using SEM-EDX is recommended to evaluate the specimen after failure. [ABSTRACT FROM AUTHOR]

The unstable meso-structure of preform affects the mechanical properties of 3D angle-interlock woven composites, which restricts the application in load-bearing component. To enhance the elastic properties of composites, the modified curing processes were proposed to improve the structural stability of preform. Two typical methods of the modified curing processes were described in this research, and three typical composite samples were manufactured. The influence of different curing processes on meso-structural characteristic and mechanical properties of composites was investigated. Then, the quasi-static tensile and three-point bending tests were carried out, and the load–deflection curves and stress–strain curves were obtained. The failure modes and damage mechanisms of three typical composite samples were analyzed. The results showed that the modified curing process improved the structural consistency of preform, and the straightness of load-bearing yarns increased. The elastic modulus of samples was increased by about 20% ~ 35% with the modified curing process, which effectively reduced the variation coefficient of the strength and modulus. The modified curing process reduced the crimp percentage of load-bearing yarns, which increased the bonding strength between fibers and epoxy. The load-bearing carbon fibers were completely used in composites, and the results could broaden the application of composites in structural components. [ABSTRACT FROM AUTHOR]

The fiber optical current transformer (FOCT) has distinguishing advantages of small size,simple insulation,no magnetic saturation. It can be better compatible with modern digital control and protection systems,which has become an important development direction of current transformer. However,the reliability of FOCT in long-term operation is low at preasent,so its popularization and application in digital substations is seriously restricted. In this paper,the fault tree analysis of FOCT is comprehensively carried out from both the circuit and the optical path,and a fault mode analysis system covering the overall structure of FOCT is established. Firstly,the structure and operating principle of FOCT are analyzed,and the fault is divided according to its circuit composition. Secondly,the main fault modes occurring in the long-term operation of FOCT are extracted,and the listed fault modes are investigated one by one. Then,the reliability improvement measures are proposed from the aspects of scheme design,component selection and construction technology. Finally,the fault tree is used to analyze the cause of a light source fault combining with an actual case,and the reliability improvement measures are proposed to verify the effectiveness of the proposed method. The research can provide a theoretical basis for FOCT fault analysis and operation reliability.

A failure risk assessment must be carried out and potential drilling equipment failure risks must be promptly addressed in order to prevent drilling fluid pollution during offshore oil drilling. The qualitative, comprehensive, and quantitative failure risks for Drilling Permanent Magnetic Synchronous Motors (DPMSM) are examined in this article using a hybrid methodology. First, the Drilling PMSM using Failure Mode Analysis (FMA) method is combined with the Risk Matrix (RM) approach to analyse the risk levels of risk factors individually. Next, the Borda number is introduced to compare the risk levels exactly. To execute a Fuzzy Comprehensive Evaluation (FCE) of the system failure risk, a fuzzy relation matrix of risk factors is generated, and the weight of each risk component is calculated using importance analysis. The failure rate is then determined using fuzzy inference, and the Fault Tree (FT) is then built based on the risk variables. Fault tree analysis is used to compute the system failure rate, and the significance of the bottom event is evaluated. The Bayesian network (BN) is used to depict the Fuzzy Fault Tree (FFT) analysis. By utilizing Bayesian forward causal inference and reverse diagnostic inference to calculate the leaf node failure rate and root node posterior probability, the system's weak points and potential failure causes are determined. [ABSTRACT FROM AUTHOR]

Fabric-reinforced cementitious matrix (FRCM) composites, also known as textile-reinforced mortars (TRMs), represent a new advancement in structural repair and reinforcement technology. Aiming to improve the energy efficiency and seismic performance of existing buildings, this research focused on the development of an FRCM system in combination with phase change materials (PCMs) and extruded polystyrene sheets (XPS) to achieve adequate mechanical and thermal properties for reinforced concrete (RC) and masonry structures. Accordingly, the in-plane behaviour of five FRCM-strengthened RC frames with hollow-brick wall infill was tested under cyclic loading to investigate the improvement in earthquake resistance. The system was comprehensively evaluated by calculating hysteresis curves; comparing the lateral stiffness, ductility, and energy dissipation capacity; measuring the deformations of the specimens; and analysing the failure modes mechanically. Finally, it was proved that this novel integrated approach could significantly enhance the mechanical and seismic performance of masonry-infilled RC frames. [ABSTRACT FROM AUTHOR]

The aim of this paper is to propose a new approach allowing the improvement of the operation, the performances and the lifetime of a photovoltaic system. This improvement concerns the energy storage system, and it is essentially ensured by a multi-criteria analysis integrating the dependability analysis tools. In this context, this approach is based on an evaluation focused on several selection criteria and several technical factors to properly determine the most relevant technology for solar batteries such as lead–acid battery, nickel–cadmium battery (Ni–Cd), nickel–metal hydride (Ni–MH) battery and lithium-ion battery. The factors that are taken into account by the authors in this multi-criteria analysis are reliability, security, size and cost. The assessment of the reliability of the available battery capacity is established using failure modes, effects and criticality analysis and a classification of failure modes by an appropriate calculation of the number risk priority (RPN). The analysis of the security criteria is based on the development of a preliminary risk analysis which shows the impact of different solar technologies batteries on the environment, human health and physical. This approach is also interested in the evaluation of the cost and the impact of the volume, the number and the mass of the batteries used in the photovoltaic system. Finally, this approach is completed by the utilization of the Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE) to develop a decision-making model and solve the problem of choosing solar battery technology. [ABSTRACT FROM AUTHOR]

Abstract The battery management system (BMS) is the main safeguard of a battery system for electric propulsion and machine electrification. It is tasked to ensure reliable and safe operation of battery cells connected to provide high currents at high voltage levels. In addition to effectively monitoring all the electrical parameters of a battery pack system, such as the voltage, current, and temperature, the BMS is also used to improve the battery performance with proper safety measures within the system. With growing acceptance of lithium-ion batteries, major industry sectors such as the automotive, renewable energy, manufacturing, construction, and even some in the mining industry have brought forward the mass transition from fossil fuel dependency to electric powered machinery and redefined the world of energy storage. Hence, the functional safety considerations, which are those relating to automatic protection, in battery management for battery pack technologies are particularly important to ensure that the overall electrical system, regardless of whether it is for electric transportation or stationary energy storage, is in accordance with high standards of safety, reliability, and quality. If the system or product fails to meet functional and other safety requirements on account of faulty design or a sequence of failure events, then the environment, people, and property could be endangered. This paper analyzed the details of BMS for electric transportation and large-scale energy storage systems, particularly in areas concerned with hazardous environment. The analysis covers the aspect of functional safety that applies to BMS and is in accordance with the relevant industrial standards. A comprehensive evaluation of the components, architecture, risk reduction techniques, and failure mode analysis applicable to BMS operation was also presented. The article further provided recommendations on safety design and performance optimization in relation to the overall BMS integration.

The exploration of traffic areas as a novel photovoltaic integration opportunity within the traffic sector, specifically in road surfaces, has been demonstrated in various projects. Limited data and publications about the performance and failure modes of these innovative road-integrated modules highlights the need for a comprehensive failure analysis. This study focuses on first time assessing failure modes of road-integrated photovoltaic modules installed at Austria's first road-integrated PV system in Teesdorf. A comprehensive failure mode analysis is conducted at the 100 m2 PV parking place using a combination of quantitative and qualitative methods. These methods include regular visual inspections, I-V-curve measurements at both string- and module-levels (with a simplified STC correction), electroluminescence- and dark-I-V-curve measurements, and the use of monitoring data. The PV parking place produced 10.2 MWh in its first operation year, 27.18% less than the estimated yield. Visual inspections reveal various failure modes, including detachment of the module top layer, delamination, and broken module edges. In the analysed monitoring data continuous power losses are observed over the systems operation time. String-level power losses of up to 47.8% (mean: 33.5%) are calculated for the first year of operation. For the second year of operation the power losses reach a up to of 77.5% (mean: 56.2%). Cell cracks as the main cause of these power losses, attributed to vehicle loads, are identified through electroluminescence images. Out of 16 analysed strings with dark I-V-curve measurements three showed at least one bypass diode malfunctions. The combination of quantitative and qualitative methods identified multiple failure modes and their main causes. As a conclusion, the study highlights the challenges of integrating PV modules into road surfaces, emphasizing the need for standardisation and quality assurance in the field of road-integrated PV applications.

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Objectives: This study aimed to investigate the effect of a customized low-sodium bioactive glass (BG) fillers in experimental resin composites on their bond strength to dentin after 12 months of artificial aging. Specifically, it evaluated whether the bond strength was affected by different BG concentrations (0, 10, 20, 40 wt%) and artificial aging durations (1, 6, and 12 months)., Materials and Methods: Experimental composites were prepared with 10, 20, and 40 wt% of a customized low-sodium fluoride-containing BG. The experimental composite with 0 wt% BG was used as a control, while Beautifil II (Shofu) was used as an external reference material. A universal adhesive system was applied to dentin substrates and composite build-ups were made. Bond strength was measured using a macro-shear bond strength test, and Weibull statistics were used to assess the reliability of the materials. Failure modes were analyzed to evaluate the type of the fracture., Results: After 12 months, the bond strength of all experimental composites remained stable and comparable to the control material, with statistically significant improvements between 6 and 12 months for all experimental materials. The bond strength was statistically similar across materials, except at the 12-month point, where the 20 wt% BG-composite showed significantly higher bond strength than the 40 wt% BG-composite. The frequency of mixed failures in composite increased after 12 months, particularly in experimental composites containing higher BG content., Conclusions: The incorporation of a customized low- sodium BG into resin composites did not negatively impact their bond strength to dentin over 12 months. Instead, bond strength improved over time, and the composites remained mechanically stable, although a higher incidence of mixed failures was observed with increased BG content., Clinical Relevance: The customized low-sodium BG demonstrated stable bond strength over the 12-month period, offering a promising option for functional fillers in restorative composites without compromising the longevity of the adhesive-dentin interface., Competing Interests: Declarations. Ethical approval: Not applicable. Informed Consent: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Industrial Electron Linacs have become popular tools for a multitude of radiation technology applications in the fields of material modification, pollution control as well as national security. Although thousands of accelerators are being regularly used, failure analysis of Industrial Electron Accelerators remains a sparsely researched topic and not much information is available in public. Being an economically viable option, industrial electron accelerators need to have a 24 × 7 reliable operation. Hence, it is necessary to understand the failure modes and their mitigation techniques, so that the operation of the accelerators is stable, consistent and safe. In this study, failure mode analysis and identification of degradation mechanisms in an industrial 10 MeV RF electron linac have been studied, with emphasis on the electron gun. Failure modes of the linac and its sub-systems have been investigated. Failure Mode and Effects Analysis and Fault Tree Analysis techniques have been examined for the electron gun. Bayesian Networks are used for modelling the performance of electron gun sub system, utilising the operational data of the RF linac. This approach has facilitated the evidential reasoning process to investigate most probable mode of failure and preventive measures have been recommended for mitigation of failure. [ABSTRACT FROM AUTHOR]

Product design needs to take full account of requirements from the lifecycle of product. However, researcher considered more requirements from product manufacturing/assemble stage, and less requirements from product operation stage. Identifying subsystems to be improved and risk analysis is two methods applied to product design considering the effect of failure at product operation stage. But these methods are labor-intensive and time-consuming tasks and need a lot of expert knowledge. There are huge amounts of data including inspection reports and maintenance records in product operation stage. These data can offer meaningful feedback on next-generation product design. The past few years, digital twin has gained considerable attention because it is characterized by two-way interactions between the digital and physical worlds. This paper proposes a digital twin (DT) framework for product to-be-designed analysis based on operation data. DT data is collected and store from the operation stage of current product. DT data is processed and analyzed to acquire the operation knowledge by Clustering algorithm, Frequent Pattern-growth algorithm, Multi-attribute decision-making, etc. The failure knowledge is used for the design of next-generation product. It can help designer to identify subsystems to be improved and offer the failure information for risk analysis. The failure knowledge also predicts the easily failure subsystems at operation stage of current product. A case of Tunnel Boring Machine is given to illustrate the implementation process of the framework and realize the part function of the framework. [ABSTRACT FROM AUTHOR]

The battery management system (BMS) is the main safeguard of a battery system for electric propulsion and machine electrification. It is tasked to ensure reliable and safe operation of battery cells connected to provide high currents at high voltage levels. In addition to effectively monitoring all the electrical parameters of a battery pack system, such as the voltage, current, and temperature, the BMS is also used to improve the battery performance with proper safety measures within the system. With growing acceptance of lithium-ion batteries, major industry sectors such as the automotive, renewable energy, manufacturing, construction, and even some in the mining industry have brought forward the mass transition from fossil fuel dependency to electric powered machinery and redefined the world of energy storage. Hence, the functional safety considerations, which are those relating to automatic protection, in battery management for battery pack technologies are particularly important to ensure that the overall electrical system, regardless of whether it is for electric transportation or stationary energy storage, is in accordance with high standards of safety, reliability, and quality. If the system or product fails to meet functional and other safety requirements on account of faulty design or a sequence of failure events, then the environment, people, and property could be endangered. This paper analyzed the details of BMS for electric transportation and large-scale energy storage systems, particularly in areas concerned with hazardous environment. The analysis covers the aspect of functional safety that applies to BMS and is in accordance with the relevant industrial standards. A comprehensive evaluation of the components, architecture, risk reduction techniques, and failure mode analysis applicable to BMS operation was also presented. The article further provided recommendations on safety design and performance optimization in relation to the overall BMS integration. [ABSTRACT FROM AUTHOR]

The obtainment of the Sanitary License for Pharmaceutical Operations requires the risks analysis of quality in the manufacturing process of each product. The main aim of the present work was to apply this evaluation to the production process of freeze-dried kit for labeling with Technetium-99m of monoclonal antibodies, which are developed in the Isotope Center. The failure modes and effects analysis technique and the Cuban code SECURE-MR-FMEA version 3.0 were used. The lifting of the sub-processes, stages and failure modes was carried out through brainstorming. A task group of experts reconciled their results and determined the most influential causes. The model consists of ten sub-processes, 28 stages, and 40 failure modes. Of the 98 possible combinations, 39 Sub-Process-Stage-Failure Mode-Cause ones were identified, with a risk priority number (RPN) ≥100 and a severity index (ISev) ≥7. The most contributing sub-processes were: manufacturing, conditioning and sanitizing of the clean area, preparation of glassware and materials, and the obtaining of the water for injection. The most important causes were: qualification and training of the staff; non-compliance with practices, protocols, procedures or standards; and the use of qualified equipment. The results of the sensitivity analysis showed that the solution of these causes makes possible a significant reduction of the risks of the manufacture process and, thus, contributes the compliance with good manufacturing practices, with the priority of actions and resources in these directions. [ABSTRACT FROM AUTHOR]

The consultation on risk studies applied to practices with ionizing radiation shows the use of prospective and reactive methods, which are associated not only with advantages, but also some disadvantages. The systematic coupling of these methods can be a resource to combine the advantages and compensate for those disadvantages. The guarantee of such development requires a methodological and computer base. The objective of this work is to present Cuban computer code SECURE-MR-FMEA, its characteristics and capacities to integrate the risk matrix methods, FMEA and its own database with reactive capabilities for incident learning. The code has been developed inside the Ministry of Public Health national research project and is currently used by several national users. Likewise, to verify the system's capabilities, the data derived from the application of the failure modes and effects analysis method, according to document TG-100, to IMRT practice were introduced. Based on this approach, the results for said practice in all available modalities of risk studies are displayed and discussed. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of Er,Cr:YSGG laser treatment on microshear bond strength of zirconia to resin cement before and after sintering. Materials and Methods: Ninety pre-sintered yttrium-stabilized tetragonal zirconia specimens (4 x 3 x 2 mm) were divided into 6 groups (n = 15). In group C, sintered zirconia was not treated (control group). In groups AS2 and AS3, sintered zirconia blocks were irradiated by Er,Cr:YSGG using a power of 2 and 3 W, respectively. Groups PS2 and PS3 consisted of pre-sintered blocks conditioned by Er,Cr:YSGG at 2 and 3 W, respectively. In group AA, sintered zirconia was air abraded with 50-μm alumina powder. One block was made using the same preparations as mentioned above and was morphologically assessed by SEM. Microcylinders of Panavia F 2.0 were placed on the treated surface of the groups. Samples were incubated at 37°C and 98% humidity for 48 h and then subjected to microshear bond strength testing. The mode of failure was evaluated. Data were analyzed by one-way ANOVA and Tukey's HSD test (p < 0.05). Results: There was a statistically significant difference between group AA and the others (p < 0.0001). A significant difference was also noted between groups AS3 and C (p = 0.031). Complete surface roughness was seen in group AA and the bond failure was mostly cohesive, while in laser-treated groups, the surfaces roughness was much lower vs other groups, and the mode of failure was mostly adhesive. Conclusion: Laser treatment of pre-sintered Y-TZP cannot be recommended for improving the bond. Although sandblasting of sintered Y-TZP yielded better results than the rest of the groups, 3 W power after sintering can also be effective in enhancing the bonding strength of resin cement to zirconia. [ABSTRACT FROM AUTHOR]